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Maxwell 3D — Table of Contents

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Maxwell 3DSolversUsing the Help SystemScreen WindowsHotkeys3D Modeler

File MenuEdit MenuView MenuCoordinates MenuLines MenuSurfaces MenuSolids MenuArrange MenuOptions MenuWindow MenuHelp Menu

Material ManagerBoundary/Source Manager

Magnetostatic Boundary Conditions and SourcesElectrostatic Boundary Conditions and SourcesEddy Current Boundary Conditions and Sources

Executive ParametersSetup Solution Options

Seed MenuMesh MenuRefine Menu

Parametric Solution OptionsSolve

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Viewing Parametric SolutionsPost Processor

Post Processor MacrosGeometry MenuData MenuPlot Menu

ParametricsParametrics Post ProcessorExecutive Parameters MacrosMaxwell 3D Script CommandsTechnical NotesGlossaryTool Bar IconsMacro Editor

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Maxwell 3DMaxwell 3D Executive CommandsSetting Up A 3D ModelSetting Up and Solving A Parametric ModelSolution Monitoring AreaMenus and KeystrokesVariations in Screen Displays and CommandsBatch Processing

Batch Mode for Workstations (UNIX)Batch Log FilesBatch Script Files

Batch Mode for Windows






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Using the Help SystemThe Topics ListThe Button CommandsLinks in the TextDocument TitleActive Regions on GraphicsSelecting Text and GraphicsThe Menu BarHelp Window Functions

Page NumberScreen Size (Percentage)Screen Size (Step)Page ScrollScroll Bar






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Screen WindowsSide Window

Modifying CoordinatesEntering Data in the Side WindowsModifying Snap ToAbsoluteRelative

View WindowsCommand PromptRight Mouse Button Menu

Next BehindParallel to GridMove along AxisMove in 3DPositionRotatePanZoomSelect

Zoom InZoom OutFit AllVisibilityShow CoordsRender

Render/Wire FrameRender/Flat ShadedRender/Smooth Shaded

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3D ModelerInitializing the Drawing UnitsModifying the GeometryModeler Menu CommandsTool BarPlanning the Geometric Model

Setting Up the Modeling EnvironmentSnapsDividing a Structure into ObjectsCreating ObjectsOpening and Saving Model FilesKeep it SimpleTake Advantage of SymmetryFinal Objects Must Not OverlapSizing the Problem RegionBackgroundUnitsLevel of Detail (Aspect Ratio)Sizing Limits (Min D and Max D)Virtual ObjectsUsing 2D Objects as Thin Conductors and ResistorsUsing 2D Objects as Coil TerminalsInvalid Coil Terminals

Geometric Models for Executive ParametersForce and the Geometric ModelTorque and the Geometric ModelCapacitance Matrices and the Geometric ModelInductance and the Geometric Model

Clearly Define All Current LoopsFinding Inductance When No Loop Is Present

Impedance and the Geometric ModelSkin Depth

Solution Analysis of Geometric Models






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MacrosCreating a MacroExecuting a MacroEditing a MacroA Macro ExampleScript Instructions

IFREPEATWHILE

Measuring Distances Between Objects

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File MenuFile CommandsFile ExtensionsFile/NewFile/Open

Read Only ModeOpening Maxwell 2D Field Simulator Files version 4.33 (or earlier)

File/CloseFile/SaveFile/Save AsFile/Macro

File/Macro/Start RecordingFile/Macro/Stop RecordingFile/Macro/ExecuteFile/Macro/DeleteFile/Macro/PromoteFile/Macro/Edit Macro

File/ImportFile/Import/2D Modeler FileFile/Import/3D Modeler/ACIS FileFile/Import/Translate

Scaling and Units ConversionDesign Intent and PlanningSTEP and IGESBatch Processing with the Translator

File/ExportFile/Export/2D Modeler FileFile/Export/Old 3D ModelerFile/Export/ACIS Ver 1.7 FileFile/Export/ACIS Ver 2.1 FileFile/Export/ACIS Ver 3.0 File

File/Export AnimationFile/Print Setup






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File/PrintFile/Print/RectangleFile/Print/Active ViewFile/Print/Project

File/Apply ChangesFile/RevertFile/Exit

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Edit MenuEdit CommandsEdit/UndoEdit/RedoEdit/CutEdit/CopyEdit/PasteEdit/ClearEdit/UndeleteEdit/Duplicate

Edit/Duplicate/Along LineEdit/Duplicate/Around AxisEdit/Duplicate/Mirror

Edit/SelectEdit/Select/By NameEdit/Select/By VolumeEdit/Select/Faces Intersection

Edit/Select AllEdit/Deselect All

Deselecting Items With the MouseEdit/Attributes

Edit/Attributes/By ClickingColorNameShow OrientationModelDisplay as Wireframe

Edit/Attributes/RecolorEdit/Visibility

Edit/Visibility/Hide SelectionEdit/Visibility/By ItemEdit/Visibility/Toggle Region






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Edit/Show AllEdit/Command HistoryEdit/Clear Boundary/SourceEdit/Reprioritize Boundary/SourceEdit/Select BodiesEdit/Deselect All BodiesEdit/Select FacesEdit/Deselect All FacesEdit/Insert RowsEdit/Delete Rows

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View MenuView CommandsUsing the Mouse to Change the ViewView/Render

View/Render/WireframeView/Render/Flat ShadedView/Render/Smooth Shaded

View/Zoom InZooming In With the Mouse

View/Zoom OutZooming Out With the Mouse

View/Fit SelectionView/Fit All

View/Fit All/All ViewsView/Fit All/Active View

View/Reset Standard ViewsView/Coordinate System

View/Coordinate System/ShowView/Coordinate System/HideView/Coordinate System/LargeView/Coordinate System/SmallView/Coordinate System/Positive OnlyView/Coordinate System/Two Sided

View/Grid PlaneView/Grid Plane/ShowView/Grid Plane/HideView/Grid Plane/XYView/Grid Plane/YZView/Grid Plane/XZ

View/Setup GridView/Side WindowView/Toolbar






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View/Command PromptView/Status BarView/Save Module PreferencesView/Revert to DefaultsView/Toggle Boundary Visualization






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Coordinates MenuCoordinates CommandsUsing Coordinate Systems

GlobalLocalSaved localObjectRotated

Coordinates/Set Current CSCoordinates/Set Current CS/Move OriginRotating Coordinate SystemsCoordinates/Set Current CS/Rotate XCoordinates/Set Current CS/Rotate YCoordinates/Set Current CS/Rotate ZCoordinates/Set Current CS/Use Object CS

Coordinates/Save Current CSCoordinates/DeleteCoordinates/Set Object CSCoordinates/GlobalCoordinates/LocalCoordinates/UnrotatedCoordinates/Rotated






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Options MenuOptions CommandsOptions/UnitsOptions/Check OverlapOptions/Region

Options/Region/DefineOptions/Region/Fit AllOptions/Region/HideOptions/Region/ShowOptions/Region/VerifyBackground Object

Outer BoundariesExcluded (Non-Existent) Background

Optimal Size of the Modeling RegionOptions/Expressions

Common FunctionsDefining a FunctionChanging a FunctionDeleting FunctionsDataset

Options/Default ColorOptions/Selection ColorOptions/Preferences

3D Post Processor Preferences






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Help MenuHelp CommandsHelp/About HelpHelp/On ModuleHelp/On Maxwell 3DHelp/On ContextHelp/ContentsHelp/IndexHelp/TutorialHelp/Shortcuts

Help/Shortcuts/HotkeysHelp/Shortcuts/Tool Bar

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Material ManagerModifying the Material SetupAssigning MaterialsMaterial Database

Global Material DatabaseLocal Material DatabaseInheritance

Adding Materials to the DatabaseAssigning Materials to Objects

Functional and Vector Material ProperiesAlign with Object’s OrientationAlign Relative to Object’s OrientationAlign with a Given Direction

Excluded ObjectsExcluding and Including Background Objects

Changing Material AttributesDeleting Materials

Deleting Derived MaterialsUnderiving and Rederiving Materials

Material AttributesRelative PermittivityRelative PermeabilityConductivityImaginary PermeabilityMagnetic CoercivityMagnetic RetentivityMagnetization

Selecting Several Objects at OnceDeselecting ObjectsHelp MenuPerfect ConductorsAnisotropic Materials






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Anisotropic Permittivity TensorAnisotropic Permeability TensorAnisotropic Conductivity TensorAnisotropic Imaginary Relative Permeability Tensor

Permanent MagnetsNonlinear vs. Linear Permanent Magnets

Nonlinear MaterialsAdding Nonlinear MaterialsEntering a BH-CurveDeleting a BH-CurveModifying B and H values for a BH-CurveAdding Points to a BH-CurveImporting a BH-CurveExporting a BH-CurveAxesViewNonlinear Permanent Magnets

In Air DemagnetizationIn Device DemagnetizationOther Device Considerations

Functional Material PropertiesOptionsDependent and Independent (Editable) Material Properties

Magnetostatic PropertiesElectrostatic Properties

FunctionsModifying a FunctionDeleting a Function

Vector FunctionsRadial Vector FunctionsTangential Vector Functions

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Boundary/Source ManagerModifying Boundary Conditions and SourcesEddy Current BoundariesSelecting Objects and Faces

Selecting With the MouseNext BehindSelect AllDeselect AllBy Box

Picking Objects, Faces, or BoundariesSelecting Existing Boundaries and SourcesThings to Consider

Selecting the Edges of the Problem RegionSelecting Objects and Surfaces That Lie Inside Other Objects

Tool Bar FunctionsBoundary/Source Manager Menu Commands

Model CommandsModel/FunctionsModel/UnitsModel/Set Eddy Effect

Setting Displacement CurrentsModel/Pick TerminalsModel/Show Conduction PathsModel/Verify Conduction Paths

Defining Boundaries and SourcesFunctional Boundaries and Sources

Defining a Functional Boundary or SourceUnitsOptionsFunctions of Position

Setting the Eddy EffectEddy Effect and AC Magnetic Field Behavior

Required Field Sources and References






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Electrostatic Sources and ReferencesRequired DC Electric Field SourcesRequired References for Electric Potential

Magnetostatic Sources and ReferencesRequired DC Magnetic Field SourcesReference for DC Magnetic Fields

Eddy Current Sources and ReferencesRequired AC Magnetic Field SourcesReference for AC Magnetic Fields

Electrostatic Boundary ConditionsDefault Boundary ConditionsVoltageSymmetryMasterSlave

Electrostatic SourcesFloating ConductorVoltageChargeCharge Density

Magnetostatic Boundary ConditionsDefault Boundary ConditionsH Field (Magnetic Field)InsulatingSymmetryMasterSlave

Magnetostatic SourcesVoltageVoltage DropCurrentCurrent DensityCurrent Density Terminal

Eddy Current Boundary ConditionsDefault Boundary Conditions






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H Field (Magnetic Field)SymmetryMasterSlaveInsulatingImpedance

Eddy Current SourcesCurrentCurrent Density TerminalCurrent Density






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Magnetostatic Boundary Conditions and SourcesMagnetostatic Boundary Conditions

Default Boundary ConditionsNaturalNeumann

SymmetryOdd Symmetry (Flux Tangential)Even Symmetry (Flux Normal)

H Field (Magnetic Field)Violating Ampere’s LawSuperpositionDisconnected Magnetic Field and Even Symmetry Boundaries

MatchingMasterSlaveWhen to Use Matching Boundaries

InsulatingMagnetostatic Sources

VoltageVoltage DropCurrentCurrent DensityCurrent Density Terminals

Zero Divergence






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Electrostatic Boundary Conditions and SourcesElectrostatic Boundary Conditions


VoltageSurface Potential and Field SolutionsModeling Thin Conductors

SymmetryEven Symmetry (Flux Tangential)Odd Symmetry (Flux Normal)

MatchingMasterSlaveWhen to Use Matching Boundaries

Electrostatic SourcesFloating ConductorVoltageCharge

Charge on ConductorsCharge on Dielectrics

Charge DensityCharge Density in Dielectrics






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Eddy Current Boundary Conditions and SourcesEddy Current Boundary Conditions


H Field (Magnetic Field)Symmetry

Odd Symmetry (Flux Tangential)Even Symmetry (Flux Normal)

InsulatingMatchingImpedance

When to Use Impedance BoundariesEddy Current Sources

CurrentCurrent DensityCurrent Density Terminals






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Executive ParametersExecutive Parameters CommandsExecutive Parameters Menu CommandsExiting an Executive Parameters CommandTool BarMatrix

The Return Path for CurrentForceTorqueSelect Matrix Entries

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Setup Solution OptionsFinite Element Meshing

Need for a Fine MeshMeshmaker Sizing Limits (Min D)

General ProcedureStarting Mesh

InitialCurrent

Manual MeshMeshmaker Tool Bar FunctionsMeshmaker CommandsSolver Type

ResidualsLinear ResidualNonlinear Residual

FrequencySolution TypesSolve For Fields and ParametersAdaptive Analysis

Adaptive SolutionNon-Adaptive SolutionPercent Refinement Per PassStopping Criterion

Number of Requested PassesPercent Error

Conduction Percent Error and AnalysisConvergence of the Conduction Solution

Suggested ValuesMeshing Errors

Glossary of TermsBodyLump






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ShellFaceLoopEdgeAspect Ratio

Description of AnalysesModel AnalysisContact AnalysisProximity Analysis

Common Workarounds and Fixes






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Parametric Solution OptionsParametric Solution Options Menu Commands

Variables CommandsVariables/AddVariables/DeleteVariables/View

Data MenuData Commands

Data/FillData/SweepData/Sort

Entering and Revising Data ValuesSave FieldsSetup Variables Tool Bar






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SolveSolve Commands

Solve/Nominal ProblemSolve/Variables

Viewing the ModelZoom InZoom OutFit AllVisibilityFlat ShadedWireframe

Aborting a SolutionErrors in SolutionsTemporary Solver WindowsViewing Solutions

VariablesModelSolutions

Solutions/ForceSolutions/TorqueSolutions/Matrix

ConvergenceProfile






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Post ProcessorPost Process/Nominal Problem CommandsPost Processor Tool BarHotkeysUnitsPost Processing

Geometries (Points, Lines, Surfaces, and Volumes)Plotting Common Field QuantitiesSaving and Reading PlotsCalculating Derived Field QuantitiesPlotting Derived Field QuantitiesSuperimposing Field Solutions

Post Processor MacrosCreating a MacroExecuting a MacroEditing a MacroA Macro Example

Predefined Surfaces, Volumes, and ListsPredefined SurfacesPredefined Volumes and Object Lists






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Geometry MenuGeometry CommandsGeometry/Create

Geometry/Create/PointGeometry/Create/LineGeometry/Create/ArcGeometry/Create/Cutplane

Change the Plane’s OriginChange the Plane’s Normal

Geometry/Create/Surface ListGeometry/Create/Faces ListGeometry/Create/Object ListGeometry/Create/Volume Box

Geometry/ModifyGeometry/Modify/Point

Change the Point’s NameChange the Point’s Location

Geometry/Modify/LineGeometry/Modify/CutplaneGeometry/Modify/Faces ListGeometry/Modify/Object List

Geometry/Delete

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Data MenuData CommandsData/Set Solution TypeData/Functions

Data/Functions/EditCommon Functions

Data/Functions/ModifyModifying a Variable

Data/CalculatorData CalculationsThe Calculator StackRegisters

Enlarging the Register Display AreaStack Commands

PushPopRlDnRlUpExchClearUndo

NameDegreesRadiansInput

QtyElectrostatic Field QuantitiesMagnetostatic Field QuantitiesEddy Current (AC Magnetic) Field Quantities

GeomConstNumFuncRead

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General+ (Add)– (Subtract)* (Multiply)/ (Divide)NegAbsCmplx

RealImagCmplxMagCmplxPhaseCmplxRCmplxIConjAtPhase

SmoothDomain

ScalarVec?1/x (Inverse)Power(Square Root)Trigd/d? (Partial Derivative)(Integral)∇ (Gradient)IsoMaxMin

VectorScal?Matl

Electrostatic PropertiesEddy Current Properties






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Magnetostatic PropertiesMagDotCrossDivgCurlTangentNormalUnit Vec

NormalTangent

OutputDrawPlotAnim2D PlotValueEvalWriteExport

Export/To FileExport/To Grid

Data/Solution InfoTypeMesh SizeRegion ExtentsObject NameTetrahedraTotal VolumeMin Tet VolumeMax Tet Volume

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Plot MenuPlot CommandsPlot/MeshPlot/Field

Create the GeometryPlot Quantity

Electrostatic Field QuantitiesMagnetostatic Field QuantitiesEddy Current Field Quantities

On GeometryIn Volume2D Line Plot3D Line PlotPhasePhase AnimationScalar Surface and Volume PlotsVector Surface PlotsScalar 3D Line PlotsVector 3D Line PlotsScalar 2D Line PlotsScalar Point PlotsVector Point PlotsPlot Options

NameShow Color Key

Moving the Color KeyModifying a Plot with the Color Key

FilledPlot Scale

Auto ScaleUse LimitsDivisionsLinearLogarithmic

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Color Map TypeRampSpectrumColor Block

ValueMarkerMarker Options

TypeSizeMap SizeMap Color

ArrowArrow Options

TypeSizeMap SizeMap ColorSpacing

Num PointsColorMarkerWidthStyleShow MarkersShow LineAdd to Current Plot

Plot/AnimationCreating an Animated PlotDisplaying an Animated Plot (Plot Control Panel)Plot Animation Variables

Animation VariablesEditing an Animated PlotMaking MoviesTips and Hints For Generating Animated Plots

Space






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SpeedCutplanes - Taking PicturesChanging the Views

Rotating ViewsZooming In and Out

Plot/BH CurvesPlot/Open

Plot/Open/2D PlotPlot/Open/3D Plot

Plot/Save AsPlot/Save As/2D PlotPlot/Save As/3D Plot

Plot/ModifyPlot/VisibilityPlot/DeletePlot/Show CoordinatesPlot/Format

Plot/Format/AxesPlot/Format/Graphs






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Parametrics Post ProcessorParametrics Post Processor Commands

Parametric SetupParametrics Post Processor Tool BarVariables Plot Menu

Plot/NewPlot/OpenPlot/ClosePlot/Save AsPlot/Create Composite PlotPlot/Add GraphsPlot/Show CoordinatesPlot/Format

Plot/Format/AxesPlot/Format/Graphs

Plot/Zoom InPlot/Zoom OutPlot/Fit All

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Technical NotesSoftware ModulesFinite Element Analysis

TetrahedraSize of Mesh Versus AccuracyMesh Refinement

ElectrostaticsTheory

User InputConductorsWhen to Use the Electrostatic Field SimulatorInitial ConditionsSteady State ConditionsTime ConstantSolution Process

Electric Field EnergyCapacitance Matrix

Capacitance in Terms of Charge and VoltageCapacitance in Terms of Current and Time Varying VoltageMatrix Elements

Diagonal ElementsOff-Diagonal ElementsSymmetry

Solution ProcessLumped Capacitance

Lorentz ForceLorentz TorqueVirtual ForceVirtual Torque

MagnetostaticsTheory

Conduction Current SolutionCurrent DensityStatic Magnetic Field Solution

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Boundary ConditionsSolution Process

Magnetic Field EnergyMagnetic CoenergyInductance Matrix

Inductance in Terms of Flux Linkage and CurrentInductance in Terms of Voltage and Time-Varying CurrentMatrix Elements

Diagonal ElementsOff-Diagonal ElementsSymmetry

Solution ProcessLorentz ForceLorentz TorqueVirtual ForceVirtual Torque

Eddy CurrentTheory

PhasorsSources

AC CurrentsBoundary Conditions

AC Magnetic FieldsSolution Process

Skin DepthMagnetic Field EnergyHysteresis LossOhmic LossImpedance Matrix

Matrix ElementsDiagonal ElementsOff-Diagonal ElementsSymmetry

Solution ProcessInductance






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ResistanceLine Impedance

AC Inductance and ResistanceLorentz ForceLorentz TorqueVirtual ForceVirtual TorqueAverage ForcePhasor Notation

Real and Imaginary Components

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Maxwell 3DTopics:

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Maxwell 3DMaxwell 3D Executive Com-mands

Setting Up A 3D ModelSetting Up and Solving AParametric Model

Solution Monitoring AreaMenus and KeystrokesVariations in Screen Displaysand Commands

Batch ProcessingBatch Mode for Worksta-tions (UNIX)

Batch Log FilesBatch Script Files


Maxwell 3DMaxwell 3D (shown below) is an interactive software package for analyzing electric andmagnetic fields in three-dimensional structures.

When you open a project, a window similar to the following one appears:

Using Maxwell 3D, you can compute:

• Static electric fields, forces, torques, and capacitances due to voltage distributionsand charges.

• Static magnetic fields, forces, torques, and inductances due to DC currents, staticexternal magnetic fields and permanent magnets. Fields can be simulated instructures that contain linear and nonlinear materials.


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• Time-varying magnetic fields, forces, torques, and impedances due to AC currentsand oscillating external magnetic fields.

The software’s generalized, finite element based field solvers enable you to simulate elec-tric and magnetic fields in virtually any type of device. You are expected to draw the struc-ture and specify all relevant material characteristics, boundary conditions and sources, aswell as any special quantities to be computed (such as forces and torques). Maxwell 3Dthen generates the necessary field solutions and computes the requested quantities ofinterest. You can view and analyze the fields in the device using the software’s post-pro-cessing features.



Solution Monitoring AreaMenus and KeystrokesVariations in Screen Dis-plays and Commands





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Maxwell 3D Executive CommandsThe commands on the Maxwell 3D Executive Commands menu are:

Solver Selects the field quantity to be computed.Draw Creates the geometric model of a 3D structure.Setup Materials Assigns material properties to the objects in your model.Setup Boundaries/Sources

Defines boundary conditions and sources of electric or magneticfields in a model. Boundary conditions specify the field behaviorat the edges of the problem region and object interfaces. Alsospecifies charges, currents, or voltages on objects or surfaces.

Setup ExecutiveParameters

Specifies quantities to be computed during the solution process.Depending on the field, the following may be selected: force,torque, capacitance, inductance, and impedance.

Setup Solution Specifies the criteria for the model’s field and nominal solutionsor for a parametric solution.

Solve Generates nominal and/or parametric solutions for the model.Post Process Displays a post processor that allows you to:

• Plot, manipulate, and analyze field solutions.• Plot and analyze the results of a parametric sweep.

Variables Displays any parametric sweeps that have been defined.Model Displays the geometric model.Solutions Displays results of force, torque, or other executive parameters.Convergence Displays convergence information for the solution.Profile Displays profile statistics (such as memory usage) for solutions.Zoom In Zooms in toward the object, expanding the view of the object.Zoom Out Zooms away from the object, shrinking the view of the model.Fit All Fits the entire model in the view window.Visibility Displays parts of the model in the view window.Render Shows the model as wireframe, flat shaded, or smooth shaded.Help Accesses the online documentation.Exit Exits Maxwell 3D.

Maxwell 3DMaxwell 3D ExecutiveCommands







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Setting Up A 3D Model> To set up a 3D model and simulate the fields inside it, follow this general procedure:

1. Under Solver, choose the type of field to be computed (Electrostatic,Magnetostatic, or Eddy Current).

2. Choose Draw to create the geometry of your model.3. Choose Setup Materials to assign materials to each object in the model.4. Choose Setup Boundaries/Sources to specify boundary conditions and sources

of charge, current, or voltage.5. Choose Setup Executive Parameters to select which quantities of interest —

forces, torques, or capacitance matrices — are computed during the solution.6. Choose Setup Solution/Options to specify how the Maxwell 3D computes the

field solution and requested parameters. You also have the option to manuallyrefine the finite element mesh in areas of interest. Choose Setup Solution/Variables to specify the variables you assign to your model.

7. Choose Solve/Nominal Problem to compute the electric or magnetic fields insidethe structure. Choose Solve/Variables to compute the solutions for the variablesyou assigned.

8. After computing a solution, use the following commands to view information aboutit and analyze it:• Choose Convergence to display convergence statistics for the solution.• Choose Solutions to view forces, torques, capacitances, inductances, or

impedances that were computed during the solution.• Choose Post Process/Nominal Problem to view and quantitatively manipulate

the field solution. Choose Post Processor/Variables to manipulate the variablesyou assigned in the Setup Solution/Variables step. Choose Post Process/Export Circuit Equivalent to export the field solution to a file.

In general, these commands must be chosen in the sequence listed above. For example,the Setup Materials command is operable only after a geometric model has been cre-ated using the Draw command. Likewise, the Post Processor command is operable onlyif a field solution has already been generated using the Solve command. A check markappears next to the steps that have been successfully completed.



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This process is summarized below:

Select solver type

Draw geometric model

Assign materials

Assign sources and boundary conditions

Yes

No

Request that force, torque

Set up solution criteria and

Generate solution

Inspect parameter solutions; view

Compute otherquantities during

solution?

capacitance, inductance orimpedance be computed

(optionally) refine the mesh

solution information; display field plotsand manipulate basic field quantities

during solution process








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Setting Up and Solving A Parametric ModelIf you have purchased the 3D Parametrics module for the Maxwell 3D, you can access theparametric commands. These commands will allow you to set up a parametric solutionand execute a parametric analysis in the Post Processor.

After completing the model, assigning the materials, boundaries, and sources, you willwant to solve for a specific parameter or set of parameters. This is done with the SetupSolution/Variables command.

After you have solved the variables solution with the Solve/Variables command, you cananalyze your results in the Post Processor. The Post Processor allows you to plot and cal-culate your parametric data. Choose Post Process/Variables to execute any post pro-cessing parametric analyses.

If you have not purchased the 3D Parametrics module, any parametric functions will be“grayed-out” and inactive. Consequently, you will not be able to access these features.

Solution Monitoring AreaThe Solution Monitoring Area appears below the model window in the Executive Com-mands window.

When you generate a solution using the Solve command, a progress bar appears in thisarea. The bar displays how much of the solution has been calculated.

An Abort button also appears while the solution is generated. Choose this button to stopthe solution. If you choose to continue the solution, the calculations resume in the passwhere the problem was aborted.

Menus and KeystrokesWhen you choose a command from a pull-down menu, you will notice that one of the let-ters in each menu command is underlined. As an alternative to using the mouse, you canenter this letter from the keyboard to execute the command. Entering the letter only worksif the menu is pulled down.

You will also notice a keystroke combination to the right of the command. This hotkey exe-cutes the command without pulling down the menu.








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Variations in Screen Displays and CommandsThe screen captures taken in the online documentation are based on the Unix Worksta-tion version of Maxwell 3D and may vary from your actual screens if you are using a PC.

Another difference between the PC version and the Workstation version of Maxwell 3D isthe way in which active elements are displayed in the pull-down menus. In the UNIXWorkstation version, a box appears next to the active elements, while the PC version dis-plays check marks next to the active elements. For example, if you activate the commandprompt in the UNIX Workstation version, a box appears next to the View/CommandPrompt command. If you activate the command prompt in the PC version, a check markappears to this menu command.

The way in which you can multiselect items also varies in the different versions. In theUnix Workstation version, you can multiselect items by clicking on each item to highlight it,then choose a button to confirm the selection. In the PC version, you multiselect the itemsby holding down the shift key and choosing the items.








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Batch ProcessingAs an alternative to running Maxwell 3D interactively, you can use the software’s batchprocessing feature to generate field solutions for your 3D models.

> In order for the batch mode to work properly, do the following for each model:1. Select the type of field to be computed.2. Create a model, define the materials, and set up the boundaries.3. Enter your solution parameters.

To use post processing macros during a batch solution, generate a nominal solution forthe problem and define the macros before running the batch job.

Batch Mode for Workstations (UNIX)

To run the software in batch mode, enter the following commands at the UNIX prompt:

• To generate a solution for the nominal problem, enter:

m3dfs -batch projectname

• To generate a solution for the parametric sweep, enter:

m3dfs -batch variables projectname

where projectname is the name and directory path of Maxwell 3D project that you wish tosolve. Use a script to generate batch solution for multiple projects.

Batch Log Files

When you first run a batch job, the system creates a file named batch.log in the user’shome directory. Log entries for further batch jobs are appended to the end of this file. Thisfile lists:

• The time that the batch job begins.• The name and directory path of the project that is being solved.• Whether the solution is completed successfully.• Any error messages that are generated during the solution.

If your batch job fails to solve the problem, examine this file to see what caused the error.








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Batch Script Files

To run multiple batch jobs, you should create a UNIX script file. For instance, to generatein batch mode for the projects called Motor1 and connect (both in the directory ~/3dpjt),create the following script file using any UNIX text editor:

m3dfs -batch ~/3dpjt/motor1;

m3dfs -batch ~/3dpjt/connect;

When executed, this script file generates solutions for each batch job sequentially.


Batch processing for nominal problems works similarly in Microsoft Windows. The log filesare identical to those on workstations. In both Windows NT and Windows 95, the softwareautomatically looks for the environment variables HOMEDRIVE and HOMEPATH. If thesevariables are not set, batch.log will be created in the /windows directory.

To generate batch solutions in the Windows version of the software, do one or both of thefollowing:

• To generate a solution for the nominal problem using the Windows command shell,enter the following at the command prompt:

path\m3dfs -batch projectname

• To generate a solution for the parametric problem using the Windows command shell,enter the following at the command prompt:

path\m3dfs -batch variables projectname

where path is the drive and directory path where the Maxwell 3D executables are installed(for example c:\win32app\maxwell) and projectname is the drive, directory path, and nameof the Maxwell 3D project that you wish to solve.






Batch Mode for Win-dows


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SolversBefore you begin to draw the models in your project, choose which field solver to use forit. Each solver requires a different type of problem setup. If you later change the solver, allproblem setups will become invalid, and all solutions will be deleted. Because of this, it isa good idea to decide on a solver before starting.

> To choose a solver:1. Select the pull-down menu next to the label Solver.2. Select a solver from the menu.

ElectrostaticThe electrostatic field simulator computes static electric fields due to:

• Stationary charge distributions.• Applied potentials.

The quantity for which the electrostatic field simulator solves is the scalar electric poten-tial, φ; the electric field (E-field) and the electric flux density (D-field) are automatically cal-culated from the potential. Derived quantities such as forces, torques, energy, andcapacitance may be calculated from these basic field quantities.

SolversElectrostaticMagnetostaticEddy Current


Maxwell 3D — SolversTopics:

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MagnetostaticThe magnetostatic field simulator computes static magnetic fields. The source of thestatic magnetic field can be:

• DC currents in conductors.• Static external magnetic fields represented by boundary conditions.• Permanent magnets.

The quantities for which the magnetostatic field simulator solves are the magnetic field, H,and the current distribution, J; the magnetic flux density, B, is automatically calculatedfrom the H-field. Derived quantities such as forces, torques, energy, and inductance maybe calculated from these basic field quantities.

Eddy CurrentThe eddy current (AC magnetics) field simulator computes time-varying magnetic fieldsthat arise from:

• AC currents in conductors.• Time-varying external magnetic fields represented by boundary conditions.

The quantity for which the eddy current field simulator solves is the magnetic field, H. Themagnetic flux density, B, is automatically calculated from the H-field. Derived quantitiessuch as forces, torques, energy, losses, and impedances may be calculated from thesebasic field quantities at different frequencies.

SolversElectrostaticMagnetostaticEddy Current


Online Help SystemTopics:

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Using the Help SystemThe Topics ListThe Button CommandsLinks in the TextDocument TitleActive Regions on Graph-ics

Selecting Text and Graph-ics

The Menu BarHelp Window Functions

Page NumberScreen Size (Percent-age)

Screen Size (Step)Page ScrollScroll Bar

Using the Help SystemThe following sections discuss the interface of the online help system, and give helpfuladvice on using each feature of the system.

The Topics List

The topics list shows topics that are available from the current document. It also highlightswhich topics are currently being viewed. As you move through the help system, the list willchange to display the most detailed list of topics possible.

> To go to the section describing a topic in the list:• Click on the topic in the list.

As you go further into detail, you may lose track of where you are in the “information tree”.The first topic in the list will typically have a higher order list of topics, so by repeatedlyclicking on the first item you can travel up the tree. You can also use the table of contentsto navigate through the manual.

The Button Commands

Links in the Text

Links in the text are always blue. You can follow a hypertext link in the text by clicking on itwith the mouse button. The link will highlight as you click on it, and the command will beexecuted when you release the mouse button. If you move the mouse pointer off of thelink before you release the button, the command will not be executed.

Forward &Backward

These buttons move you forward and backward by one page in the cur-rent document.

Go Back Every time you click on a hypertext command to jump to a new location,the history of where you’ve been is updated. This takes you back onehypertext jump.

Contents Takes you to the table of contents for the current document. If you arein a table of contents already, this takes you to a higher level document.

Index Takes you to the Index of topics.



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Using the Help SystemThe Topics ListThe Button CommandsLinks in the TextDocument TitleActive Regions onGraphics

Selecting Text andGraphics




Document Title

The document title helps you to keep track of where you are in the help system.

Active Regions on Graphics

Often, a screen capture or other diagram will have active regions. These active regionsexecute hypertext commands when you click on them. The region will highlight when youclick on it, and as you release the button, the command will be executed. If you move themouse pointer off of the link before you release the button, the command will not be exe-cuted.

By holding down the mouse button and moving the mouse around, you can see where theactive regions of a graphic are.

Selecting Text and Graphics

If you hold down the Control key on your keyboard, the cursor will change to allow you toselect text and graphics.

> To select document text:1. Hold down the Control key and click the left mouse button where you wish to begin

selecting text.2. Drag the mouse to the end of the text you wish to select.

If you select any text that contains anchored graphics frames, the graphics will becomeselected as well.



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The Menu Bar

The following commands appear in the menu bar:

File These commands perform various file operations.Open Open another document for viewing.Print Print the current document.Close Close the current document window.

Edit These commands are used on the document text and graphics.Copy Copy the selection to the paste buffer.Copy Special Copy various formats from the selection to the paste

buffer, without copying the selection itself.Select All Select every object on the page, or all of the text in the

document, depending on what is selected.Find Search the current document for a specific string, or

other document feature.Navigation These commands affect which page of the document is displayed in the

help window. None of the commands affect the hypertext history exceptfor the Go Back command.Go To Page Go to a specific page in the current document.Next Page Go to the next page in the current document.Previous Page Go to the previous page in the current document.First Page Go to the first page in the current document.Last Page Go to the last page in the current document.Go Back Undo the last hypertext jump in the history.DocumentWindows

This cascading menu lists all of the documents thatare currently open in the viewer.

Zoom These commands affect the view of the document and its window.Zoom In Make the view of the current document more detailed.Zoom Out Make the view of the current document less detailed.Fit Page Fit the page size to the current size of the window.Fit Window Fit the size of the window to the current page size.Zoom to 100 Set the magnification to 100%, the default.



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Help Window Functions

Once you have accessed the online documentation, you can change the display of thedocumentation window in the following ways:

Page Number

Use this button to choose the page you wish to be on:

> To choose a page:1. Select the Page Number button.2. Enter the page you wish to go to.3. Choose Go.

You are taken to the page you specified.

Screen Size (Percentage)

Use this button to specify the size of the documentation window.

> To specify the size of the documentation window:1. Select the Percentage button. A list of percentage sizes appears.2. Select the percentage size you refer for the documentation window.3. Select Fit Window to Page to fit a border to the documentation window.

You can set the steps of the percentage by choosing Set at the bottom of the percentagelist.

Page Number This button allows you to choose the page you wish to be on.Screen Size(Percentage)

Choose this button to change the size of the documentation window byselecting a percentage size.

Screen Size(Step)

Choose one of the Z buttons to shrink or expand the documentationwindow by one step.

Page Scroll Choose these arrow page buttons to scroll the documentation up ordown by one page.

Scroll Bar Use the scroll bar allows to scroll through the documentation fasterthan using the page scroll buttons.



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Screen Size (Step)

These buttons specify the size of the documentation window by steps. These steps arespecified in the percentage button menu.

> To increase the size of the documentation window:1. Select the large Z button.2. Select the percentage button.3. Choose Fit Window to Page.

The documentation window is now fitted with an appropriate border.

> To decrease the size of the documentation window:1. Select the small z button.2. Select and hold the percentage button.3. Choose Fit Window to Page.

The documentation window is now fitted with an appropriate border.

Page Scroll

Use these buttons to scroll through the online documentation one page at a time.

> To page through the online documentation:• Select the page arrow buttons.

You are taken one page forward or backward in the documentation.

Scroll Bar

Use this to scroll through the online documentation quickly.

> To scroll through the current document:1. Click and hold the scroll bar.2. Move the scroll bar to the section you wish to view in the document.

The online documentation displays the text you wish to see.


Maxwell 3D — Screen WindowsTopics:

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Modifying CoordinatesEntering Data in the SideWindows

Modifying Snap ToAbsoluteRelative

View WindowsCommand PromptRight Mouse Button MenuZoom InZoom OutFit AllVisibilityShow CoordsRenderTool BarHotkeys

Screen WindowsEach screen in divided up into many windows. These windows can allow you to changethe coordinates of the model, enter commands through the keyboard, view the model,and observe the progress of a solution.

Side WindowThe side window, usually located to the left of the project window, is where you canchange the coordinates or set the snap-to behavior of the model. This window is alsowhere many command-specific fields appear.

Use this toggle menu to select the type ofcoordinate used. You may select fromabsolute or a relative coordinates. Theselected coordinate appears as the nameof the menu. The current units are displayed

Use these fields to enter the x-, y-, orz-coordinates and the radius, distance, or angle.Notice the checkbox next to the coordinate fields.The checkbox must be selected to enable thecoordinate field. These coordinate fields are usedto enter the coordinates for a variety ofcommands.

Use these checkboxes to select the type of“snap-to” you wish to employ when selectingobjects or object artifacts (vertices, lines, faces,and so forth). When you select the Othercheckbox, a window appears allowing you toselect from a variety of snap-to options.

Use the blank area under the coordinate sectionfor entering information for many commands.Fields appear here allowing you to enterinformation specific to the command you justselected.

here.



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Modifying Coordinates

When measuring distances becomes important in constructing the model, you canchoose between an absolute or a relative coordinate.

> To change the coordinates in the side menu:1. Choose Absolute or Relative from the Abs. [units] pull-down menu. This menu’s

label displays the selected coordinate type and the current units. Absolutecoordinates set your point in reference to the origin. Relative coordinates give youthe coordinates with respect to a defined point or the cursor position.

2. Choose the field of the coordinate you wish to change. Make sure that thecheckbox next to the coordinate is selected. If it is not, select the checkbox toenable the field.

3. Enter the new value of the coordinate. The point in the view window moves to thenew location. The Rad and Ang fields display the new radius and angular values inan absolute coordinate system. The Dst and Ang fields display the distance andangle values between two points in a relative coordinate system.

Entering Data in the Side Windows

Very often, you will be asked to enter values, such as names of objects or coordinates,into the fields that appear in the side window.

> To enter a name of an object:1. Enter the name of the object in the field below the list box.2. Choose OK to confirm your selection.

> To enter coordinates:1. Do one of the following:

• Click on the blank field and enter the value of the coordinate.• Click on a point in one of the view windows. Each view window may represent a

different plane. By choosing points in two of these planes, you establish thecoordinates of the point. The values automatically appear in the coordinates fields.

2. Choose OK to confirm your selection.

You can turn off any of the fields by choosing the button next to the coordinate field.







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Modifying Snap To

The snap-to behavior defines the positioning of a point on a grid or vertex. The Grid andVertex snaps are set by default and already active.

> To select the snap-to behavior:1. Choose Other from the Snap to buttons. A window appears below the coordinates

fields.2. Select the type of Edge Snap you prefer. You may select from the following:

3. Select the type of Face Snap that you prefer. You may select from the following:

4. Choose OK to accept the snap-to behavior.

Grid inters. Allows you to set the snap at the point where the grid intersects anaxis.

Edge center Allows you to set the snaps at the central points of the edges.Arc center Allows you to set the snap at the center of an arc.

Axis inters. Allows you to set the face snap at the point where an axis crossesthe face of an object.

Face center Allows you to set the snap at the center of the face of an object.







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Absolute

This setting displays the coordinates relative to the origin (0,0,0). This is the default. Clickon a point in any window to display the point’s position. The coordinates appear in thecoordinate fields in the side window.

Relative

This setting displays the distances and coordinates relative to the previous position of the3D marker.

> To choose the relative system:1. Select a point in the view windows.2. Choose Relative from the Abs. [units] pull-down menu. This displays the current

type of coordinate system and its current units.3. Select a point in any view window.

The coordinates and distance are given relative to the initial point. The distance appearsin the Dst. field in the side window.

> To move the current position marker prior to choosing relative coordinates:1. Choose Relative from the Abs. [units] pull-down menu. This menu’s label

displays the current type of coordinates and the current units of the model.2. Enter the x, y, and z distance by which you wish to move the position marker from

its current position. This point becomes the new origin of the relative coordinates.After you enter an x, y, or z distance, the Move Marker button appears.

3. Choose Move Marker.

The current position marker moves to the new point.







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View WindowsThe view windows are where you draw and display the model. By default, there are fourview windows, one for each 2D plane, and one window that displays the entire model in3D. These four view windows comprise the Project Window. You can draw parts of themodel in any view window.

Often, you will wish to manipulate one of these windows in order to change the shading,the point of view, or other features of the view window. You can activate the window youwish to manipulate by clicking the left mouse button on it. The border around the windowwill change color to show that it is now active. Once the window is active, you can modifythe display of the objects within it.

Each view window can be rotated or zoomed to change its appearance. This is doneusing the View menu, the right mouse button menu, or the hotkeys.

Command PromptThe command prompt appears at the bottom of the module window. This is where youcan enter script commands with the keyboard as opposed to using the menu commandsor the icons. You can also view the current actions that the module executes. The com-mand prompt is shown below:

The command prompt can be accessed in the 3D Modeler, 3D Boundary Manager, Exec-utive Parameters Modules, or 3D Post Processor using View/Command Prompt.

Screen WindowsSide WindowView WindowsCommand PromptRight Mouse Button MenuZoom InZoom OutFit AllVisibilityShow CoordsRenderTool BarHotkeys



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Right Mouse Button MenuThe view of the 3D model may be manipulated by the commands accessed through theright mouse button menu. The right mouse button menu appears by clicking and holdingthe right mouse button in a view window. This menu allows you to change the perspective.

> The general procedure for using the right mouse button commands is:1. Click and hold the right mouse button anywhere on the model display. The menu

appears.2. Still holding the right mouse button, select one of the following commands:

Next Behind Selects the object behind the currently selected object.Parallel to grid Constrains the mouse to move on the selected grid plane.Move alongaxis

Constrains the mouse to move along the axis that’s perpendicular tothe selected grid plane.

Move in 3D Allows the mouse to move freely in the view windows.Position Mouse behaves as it normally does. This is the default setting.Rotate Rotates the model in space. Hold down the left mouse button to use.

Screen WindowsSide WindowView WindowsCommand PromptRight Mouse Button Menu


Zoom InZoom OutFit AllVisibilityShow CoordsRenderTool BarHotkeys



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3. Release the right mouse button to select the command. Now you can manipulatethe view according to the command you selected.

Next Behind

This option selects the object behind the currently selected object. This is useful whenyou are trying to select objects or faces in the interior of the model. You must first selectan object or face before you can use this command.

Parallel to Grid

This option constrains the mouse to move on the grid plane selected with the View/GridPlane command. For instance, if the xy-grid plane is selected, this command constrainsthe mouse to only move in the x and y directions on the grid.

Move along Axis

This option constrains the mouse to move along the axis perpendicular to the grid planeselected with the View/Grid Plane command. For instance, if the xy grid plane isselected, this command constrains the mouse to only move in the z direction. Themouse’s x- and y-coordinates would remain the same.

Move in 3D

This option allows the mouse to move freely in the view windows.

Position

Position sets the mouse to position mode, which enables you to select points in the geo-metric model. The points you can select depend on the snap-to behavior.

Pan Pans the model across the screen. Hold down the left mouse buttonto use.

Zoom Magnifies or shrinks the view. Hold down the left mouse button to use.Select Select objects with the mouse.

Note: Rotate, Pan, and Zoom can also be accessed through hotkeys.






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Rotate

Use Rotate to rotate the object around its center.

> To rotate an object in the view window:1. Choose Rotate from the right mouse button menu. An arrow replaces the cursor.2. Click and hold the left mouse button on the point you wish to turn. The object

follows the movement of the cursor.

This command may cause a slight delay in the display of the view window, particularly ifthe model is complex. Note that this command does not function in the same manner asArrange/Rotate, which changes the object’s physical location.

Pan

Use Pan to move the model in the view window.

> To pan:1. Choose Pan from the right mouse button menu.2. Click and hold the left mouse button on the model. The area you click on follows

the cursor.3. Move the cursor around the display window. The model moves with the cursor.

This command is useful in centering the object in the view windows.






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Zoom

Use Zoom to magnify or shrink the view of the model.

> To zoom in towards or away from the object:1. Choose Zoom from the right mouse button menu. A magnifying glass icon

appears.2. Click and hold the left mouse button on the display window.3. Do one of the following:

• To magnify the view, move the cursor up while holding the left mouse button.• To shrink the view, move the cursor down while holding the left mouse button.Regardless of the position of the cursor, the center of the display window ismagnified or shrunk.

This command functions similarly to the View/Zoom In and View/Zoom Out options inthe menu bar, except that you do not outline the field you wish to expand when using thecommand from the mouse menu. Instead, you zoom the entire field. You may need to usethe Pan command to center the object in the screen before zooming in on the model.

Select

Use Select to select an object.

> To select an object:1. Choose Select from the right mouse button menu. A list of all objects in the

window appears.2. Double-click on the object you wish to select. Alternatively, you can choose the

name of the object in the list and choose OK.

If the Select command is active, the following commands appear in the right mouse but-ton menu:

This command has the same function as the Edit/Select command in the menu bar.

Accept Choose Accept to accept changes to the values. This command isidentical to choosing OK to accept changes or enter values.

Cancel Choose Cancel to abort the current action.






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Zoom InUse Zoom In to magnify a region of the viewing window.

> To magnify the view:1. Choose Zoom In.2. Select a point at one corner of the region to be magnified. Click the left mouse

button on the point.3. Select a second point in a diagonal corner, using the mouse.

The selected region expands to fill the window.

Zoom OutUse Zoom Out to shrink the field of view in the viewing window.

> To shrink the view:1. Choose Zoom Out.2. Select a point at one corner of region that is to be shrunk. Click the left mouse

button on the point.3. Select a second point in a diagonal corner, using the mouse.

The current view shrinks to fit in the selected area.

Fit AllUse Fit All to display the entire plot in the viewing window.

When you select this command, the view in the active viewing window expands to includeall items in the model. The size of the window does not change.




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VisibilityUse this command to either hide or display items.

> To hide or display items:1. Choose Visibility. The following window appears:

2. Select the object to hide or display in one of the following ways:• Click on the name of the object with the left mouse button. You may select multiple

objects.• Use wildcards to select object with similar names. To do this:

a. Enter the name fragment and the wildcard in the field above Show andHide. For example, use 3D* to select all objects starting with 3D. The Showand Hide buttons change to Sel and Desel.

b. Choose Sel to select the objects and Desel to deselect the objects.3. To change the visibility status of the selected object, do one of the following:

• To hide an object, select Hide.• To display an object, select Show.

4. Choose Done when you are finished changing the settings. Objects are thenhidden or displayed accordingly.




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Show CoordsUse the Show Coords command to display information about selected points.

> To view a point’s coordinates:1. Display the desired plot. If necessary, use the Zoom In command to zoom in on a

part of the plot.2. Choose Show Coords. The cursor appears as crosshairs.3. Move the mouse to the desired point on the plot.4. Click the left mouse button. If the point is a data point on the graph, the point you

chose is marked with a box. If the point lies outside of the graph, the point youchose is marked with a cross. A window appears in the upper left corner,displaying information about the selected point.

5. To view the coordinates of additional points, do one of the following:• Repeat steps 3 and 4.• Use the left and right arrow keys to move the box along the solved points on the

graph.6. Click the right mouse button to exit the Show Coords command.




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RenderUse these commands to change how the objects in the geometric model appear. You candisplay them with:

Render/Wire Frame

Choose Render/Wire Frame to view only the skeletal structure of the objects in the activewindow. This allows you to see all sides of the object at the same time. A wire frame dis-play of a geometry is shown below:

Wire Frame Wire frame outlines (the default).Flat Shaded Flat, shaded surfaces.Smooth Shaded Smoothed, shaded surfaces.

Screen WindowsSide WindowView WindowsCommand PromptRight Mouse Button MenuZoom InZoom OutFit AllVisibilityShow CoordsRender


Tool BarHotkeys



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Render/Flat Shaded

Choose Render/Shaded Flat to shade in the solid regions of an object in flat shadedmode. In this mode, the entire object is subdivided into planar polygons. Each polygon isshaded in the same color. A shaded flat display of a geometry is shown below:

Render/Smooth Shaded

Choose Render/Smooth Shaded to shade in the solid regions of an object in smoothshaded mode. In this mode, the entire object is subdivided into planar polygons. Theshading varies across each polygon to give the impression of a smooth surface. Ashaded, smooth display of a geometry is shown below:

Screen WindowsSide WindowView WindowsCommand PromptRight Mouse Button MenuZoom InZoom OutFit AllVisibilityShow CoordsRender


Tool BarHotkeys



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Tool BarA tool bar appears in the windows of most modules and acts as a shortcut for executingvarious commands.

• To execute a command, click the mouse on a tool bar icon.• To view a brief help message on a tool bar icon, hold down the mouse button on the

icon.• To view the help message without accessing the command, move the cursor off the

icon before releasing the mouse button.



Maxwell 3D — HotkeysTopics:

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HotkeysHotkeys and the MouseMouse HotkeysList of Hotkeys

3D Modeler HotkeysAnsoft Macro EditorHotkeys

3D Boundary ManagerHotkeys

Meshmaker HotkeysParametric Table Hot-keys

3D Post Processor Hot-keys

Variables Post Proces-sor Hotkeys

HotkeysSome commands in Maxwell 3D may be accessed through “hotkeys” — keystrokes thatallow you to bypass the menu system and directly execute commands. They are generallydesignated and chosen as follows:

Hotkeys are listed on menus after the commands which they execute. For example, theWindow menu in 2D Modeler displays the following hotkeys:

> To use the hotkey to shade the wireframe objects:1. Make sure all command menus are closed. If one of the command menus is open,

click the right mouse button outside of the menu to close it.2. Press the Control and F keys at the same time.

The wireframe object is now shaded.

You may view a list of all the hotkeys for Maxwell 3D.

Hotkeys and the Mouse

When manipulating the 3D view of a model, there are a set of hotkeys you may use withthe mouse. They allow you to change the view of the model without using the right mousebutton menu.

Modifier + key Hold down the modifier(s) — such as Shift or Ctrl — and press thekey(s).

BS Press the Back Space key.Key Press the key. All hotkeys should be entered in lower case.

Note: Hotkeys are not accessible if any of the command menus are displayed.

Grid GFill Solids Ctrl+F



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3D Modeler HotkeysAnsoft Macro Editor Hot-keys





Mouse Hotkeys

Use the following hotkeys instead of the right mouse button menu.

ActionCursor Position

on DisplayWindow

Results

hold Ctrl + LMB Anywhere Rotates the view.

hold Shift + LMB Anywhere Pans the view.

Shift + double-click LMB Anywhere Centers the view.

hold Ctrl + Shift + LMB Anywhere Zoom into or out of the view.

Ctrl + double-click LMB Center Displays the front view of the model.

Ctrl + double-click LMB Top Displays the top view of the model.

Ctrl + double-click LMB Bottom Displays the bottom view of the model.

Ctrl + double-click LMB Right Displays the right view of the model.

Ctrl + double-click LMB Left Displays the left view of the model.

Ctrl + double-click LMB Corners Displays an isometric view orientatedtoward the corner you double-clickedon.

Ctrl + double-click RMB Center Displays the rear view of the model.

Ctrl + double-click RMB Corners Displays the rear isometric views orien-tated toward the corner you double-clicked on.



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List of Hotkeys

The list of hotkeys, divided by module.

3D Modeler Hotkeys

The following is a list of hotkeys for the 3D Modeler:

Hotkey Function

Ctrl + N File/New. Opens a new window. New windows will close the win-dows of any previous models.

Ctrl + O File/Open. Reads in an existing geometric model or field solution.Opening a new window will close any currently open windows.

Ctrl + W File/Close. Closes the current model or solution, deleting the win-dow it is displayed in.

Ctrl + S File/Save. Writes out a model to a set of disk files.

Ctrl + Q File/Exit. Exits the current module and returns to the ExecutiveCommands window.

Ctrl + Z Edit/Undo. Reverses the effect of the last command.

Ctrl + X Edit/Cut. Deletes the selected items, placing them in the pastebuffer.

Ctrl + C Edit/Copy. Copies the selected items to the paste buffer.

Ctrl + V Edit/Paste. Copies the contents of the paste buffer to the activeproject.

Del Edit/Clear. Deletes the selected items but does not place them inthe paste buffer.

Back Space Edit/Deselect All. Deselects all currently selected objects.



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F6 View/Render/Wireframe. Displays the objects in the geometricmodel with wire outlines.

F7 View/Render/Flat Shaded. Displays the objects in the geometricmodel with flat, shaded surfaces.

F8 View/Render/Smooth Shaded. Displays the objects in the geomet-ric model with smoothed, shaded surfaces.

= View/Zoom In. Zooms in on an area of the geometry, magnifyingthe view.

- View/Zoom Out. Zooms out of an area of the geometry, shrinkingthe view.

F View/Fit All/All Views. Changes the view to display all objects inthe geometric model.

G View/Grid Plane/Hide. Hides the grid plane. Toggles with View/Grid Plane/Show.

Ctrl + G View/Setup Grid. Sets the grid spacing and other grid settings.

F4 Window/Tile. Moves and resizes windows to display them all on thescreen at the same time.

F5 Window/Cascade. Stacks (“cascades”) windows, starting at theupper left corner of the project window.

F3 Help/About Help. Provides help on the online help system.

F1 Help/On Context. Provides help on the items you click on.

Hotkey Function



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Ansoft Macro Editor Hotkeys

The following is a list of hotkeys for the Ansoft Macro Editor:









Ctrl +F5 Edit/All Parameters. Allows you to edit all the parameters.

Ctrl +P Edit/Command Parameters. Allows you to edit the macro.

Ctrl +F7 Edit/Add Database Export Macro. Creates an export databasemacro.

Ctrl +F3 Edit/Comment. Comments a line in the macro.

Ctrl+F4 Edit/Uncomment. Uncomments a line in the macro.



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Ctrl + F Search/Find. Locates the selected text.

Ctrl + R Search/Replace. Replaces selected text with new text.

Ctrl + E View/Edit Mode. Places the editor in edit mode, allowing you to editthe macro.

Ctrl + A View/Assign Parameters Mode. Places the editor in assignparameter mode, allowing you to define the parameters of themacro.



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3D Boundary Manager Hotkeys

The following is a list of hotkeys for the 3D Boundary Manager:

Hotkey Function



Ctrl + Z Edit/Undo. Reverses the effect of the last command.

Del Edit/Clear Boundary/Source. Resets a surface to its defaultboundary conditions.

S Edit/Select/By Name. Select items by name to be edited.

Back Space Edit/Deselect All. Deselects all currently selected objects.




Ctrl + T View/Toggle BoundaryVisualization. Toggles the boundary on oroff.





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3D Boundary Man-ager Hotkeys





G View/Grid Plane/Show. Displays the grid plane (the default). Tog-gles with View/Grid Plane/Hide.






Hotkey Function



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Meshmaker Hotkeys

The following is a list of hotkeys for the Meshmaker:

Hotkey Function














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Hotkey Function



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Parametric Table Hotkeys

The following is a list of hotkeys for the parametric table:

Hotkey Function

Ctrl + N File/New. Opens a new table. New tables will close the windows ofany previous ones.

Ctrl + O File/Open. Reads in an existing parametric table. Opening a newtable will close any currently open ones.

Ctrl + W File/Close. Closes the current parametric table, deleting the win-dow it is displayed in.

Ctrl + S File/Save. Writes out a parametric table to a set of disk files.

Ctrl + Q File/Exit. Exits the module and returns to the Executive Commandswindow.




Back Space Edit/Deselect All. Deselects all currently selected items.

Ctrl + I Edit/Insert Rows. Inserts rows into the parametric table.

Ctrl +D Edit/Delete Rows. Deletes rows from the parametric table.

Ctrl + V Variables/View. Lists the variables defined in the table.



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F4 Window/Tile/All. Moves and resizes windows to display them all onthe screen at the same time.

F5 Window/Cascade/All. Stacks (“cascades”) windows, starting at theupper left corner of the project window.

Hotkey Function



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3D Post ProcessorHotkeys


3D Post Processor Hotkeys

The following is a list of hotkeys for the Post Processor:

Hotkey Function














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3D Post ProcessorHotkeys



C Data/Calculator. Accesses the solution calculator, which enablesyou to perform computations using basic field quantities.

Ctrl+N Plot/Animation. Creates an animated plot of a field quantity.

V Plot/Visibility. (Cutplane, rectangle, point, 3D line, and volumeplots.) Specifies whether plots are visible or invisible.

Ctrl+F Plot/Format/Graphs. Specifies the color, line thickness, and linestyle of a previously plotted line. Also determines the type of mark-ers displayed at solution data points, and whether the graph is visi-ble on the plot.





Hotkey Function



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Variables Post Processor Hotkeys

The following is a list of hotkeys for the Variables Post Processor:

Hotkey Function

Ctrl + N File/New. Opens a new table. New tables will close the windows ofany previous ones.

Ctrl + O File/Open. Reads in an existing parametric table. Opening a newtable will close any currently open ones.

Ctrl + W File/Close. Closes the current parametric table, deleting the win-dow it is displayed in.

Ctrl + S File/Save. Writes out a parametric table to a set of disk files.

Ctrl + Q File/Exit. Exits the module and returns to the Executive Commandswindow.




Del Edit/Clear. Deletes the selected items but does not place them inthe paste buffer.

Back Space Edit/Deselect All. Deselects all currently selected items.

Ctrl + I Edit/Insert Rows. Inserts rows into the parametric table.

Ctrl + D Edit/Delete Rows. Deletes rows from the parametric table.



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Ctrl + V Variables/View. Lists the variables defined in the table.

Crtl + P Plot/New. Draws a new plot from the data given in the data table.

= Plot/Zoom In. Zooms in on an area of the geometry, magnifying theview.

- Plot/Zoom Out. Zooms out of an area of the geometry, shrinkingthe view.

F Plot/Fit All. Changes the view to display all objects in the geometricmodel.

Ctrl + F Plot/Format/Graphs. Specifies the color, line thickness, and linestyle of a previously plotted line. Also determines the type of mark-ers displayed at solution data points, and whether the graph is visi-ble on the plot.

F4 Window/Tile/All. Moves and resizes windows to display them all onthe screen at the same time.

F5 Window/Cascade/All. Stacks (“cascades”) windows, starting at theupper left corner of the project window.

Hotkey Function


Maxwell 3D — 3D ModelerTopics:

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3D ModelerInitializing the Drawing UnitsModifying the GeometryModeler Menu CommandsTool BarPlanning the GeometricModel

Geometric Models for Execu-tive Parameters

Solution Analysis of Geomet-ric Models

MacrosMeasuring DistancesBetween Objects

3D ModelerChoose Draw from the Executive Commands menu to access the 3D Modeler. Afterselecting the field quantity you wish to compute, do the following to create (or modify) thegeometric model of a structure:

• Draw the objects in the model.• Specify the preferences of the model.• View or edit existing models.

The 3D Modeler screen appears as shown below:



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Initializing the Drawing UnitsWhen you first access the 3D Modeler, the following screen appears:

> To select the units for your model:1. Click and hold the Select Units button. This button displays the currently defined

units. A pull-down menu appears.2. Select the new set of units from the pull-down menu.3. Select the warning button to disable the warning message. This prevents the

warning from reappearing with each new model you create.4. Choose OK to accept the unit and warning settings, or Cancel to ignore the

settings and use the defaults.

Note: No matter what drawing units you select, the results will always be given inSI units.

3D ModelerInitializing the DrawingUnits

Modifying the GeometryModeler Menu CommandsTool BarPlanning the GeometricModel






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Modifying the GeometryIf you are modifying the geometry of a model for which a solution has been generated, thesystem displays the following message:

If you make changes to the geometry and save those changes,all mesh files and solution data will be deleted and will haveto be recomputed. Pick “View Only” if no changes are to besaved, “Modify” if changes are to be saved, or “Cancel” tocancel this operation.

• To change the geometry, choose Modify.• To display the geometry without modifying it, choose View Only. The 3D Modeler

screen then appears in a “view only” mode, allowing you to use commands for viewingonly the geometry.

• To return to the Executive Commands window, choose Cancel.







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Modeler Menu CommandsThe menus of commands available in the 3D Modeler are:

File Loads and saves geometric models; sets printing options; prints screencaptures; imports and exports other files; exits the 3D Modeler.

Edit Erases effects of last command; cuts, copies, and pastes objects;removes unwanted objects; duplicates objects around an axis, line, ormirror; selects and deselects objects; specifies object attributes; con-trols object visibility.

View Displays wireframe or shaded views of objects; changes the view of thegeometric model; controls how the tool bar, coordinate system axes,drawing grid, status bar, and command prompt are displayed.

Coordinates Moves, rotates, saves, and deletes local coordinate system definitions;reverts model back to global coordinate system; allows rotated andunrotated coordinate systems.

Lines Draws points, polylines, arcs, circles, and rectangles.Surfaces Detaches faces of objects; connects and stitches two object faces

together; changes outlines into covered faces and covered faces intoopen objects.

Solids Draws boxes, cylinders, helixes and other 3D objects; sweeps 2Dobjects along a path or around an axis, creating 3D objects; unites,intersects, and subtracts 3D objects, making more complex objects.Also changes open objects into sheet objects.

Arrange Moves, rotates, mirrors, and rescales objects.Options Selects units, the size of the problem region, and the default object

color; defines user preferences for modeler settings.Window Adds and deletes view windows; tiles and cascades view windows.Help Accesses Maxwell 3D’s online documentation.







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Tool BarA tool bar appears in most modules and acts as a shortcut for executing various com-mands.

• To execute a command, click the mouse on a tool bar icon.• To view a brief help message on a tool bar icon, hold down the mouse button on the

icon.• To view the help message without accessing the command, move the cursor off the

icon before releasing the mouse button.

The commands that each icon executes are represented below. Click on an icon to viewmore information about the command it represents.

In the 3D Modeler, the placement of the toolbar is controlled with the View/Tool Bar com-mands which allow you to place it on any side of the viewing windows.







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Planning the Geometric ModelThe following sections are things to keep in mind when creating a geometric model.

Setting Up the Modeling Environment

In most cases, the default setup is the best one to work with. If you find it necessary tochange aspects of the default setup, such as grid coordinates or snaps, consult the gen-eral steps below.

> To change the default absolute coordinate setup for the solid modeling environment:1. Choose Abs. A pull-down menu appears.2. Choose Relative to change from the default coordinate system to a relative one.

Enter the coordinates in the X, Y, and Z fields. You can toggle any inactive fieldsby clicking on the button next to them to make them active. By default the Grid andVert (Vertex) buttons are active.

Snaps

A snap is a location filter that allows you to set specific coordinates not given by thedefault grid and vertex settings.

> To change a snap:1. Select Other Snap from the Snap to buttons. A pop-up menu appears. Only one

snap type may be enabled at a time.2. Select the Edge Snap you prefer. Grid Intersections allows you to set the snap at

the point where the grid intersects an axis. Edge Centers allows you to set thesnaps at the central points of the edges. Arc Centers allows you to set the snap atthe center of an arc.

3. Select the Face Snap you prefer. Axis intersections allows you to set the facesnap at the point where an axis crosses the face of an object. Face Centers allowsyou to set the snap at the center of the face of an object.

4. Choose OK to accept the changes in snaps.







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Dividing a Structure into Objects

At this step in the process, the objects that you create are strictly geometric entities. How-ever, it is helpful to visualize each 3D object as a mass of material such as steel, ceramic,or air — even though the characteristics that define these materials are not assigned untillater.

For example, the geometric model shown below represents a simple conductor within ahollow coil used to study eddy currents. As a geometric model, the structure is simply aset of objects to which the names “box3d” and “object1” have been assigned. No materialattributes are linked to these objects until you assign materials to them.







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Creating Objects

The general strategy to follow in creating the three-dimensional model of an electromag-netic structure is to build it as a collection of 3D objects. Treat each different material as aseparate object.

> To create a 3D object in the 3D Modeler:1. Choose the appropriate icon for the object you wish to draw or choose the Solids

Menu from the menu bar to choose the shape of the object.2. Draw the object in any of the view windows.

Opening and Saving Model Files

By default, the model you create in the 3D Modeler is saved with the current project.

• To load geometric models from other projects, use the File/Open command.• To import 3D models in other file form, use the File/Import command.• To save the geometric model while in the process of creating it, use the File/Save or

FIle/Save As commands. File/Save will save the drawing under the established filename. File/Save As allows you to save the model under a different filename. Anychanges you make are not saved automatically.

Keep it Simple

Keep the model as simple as possible. The more complex a geometric model is, the morecomplex the finite element mesh has to be — resulting in greater requirements for mem-ory and processing power which can take longer to process a result.

Take Advantage of Symmetry

If the structure has a plane of symmetry with the field on one side of a plane being themirror image of the field on the other side, take advantage of the symmetry and only cre-ate the geometric model for half the structure. Use the Edit/Duplicate command toquickly create the other half.

When setting boundary conditions, be sure to set the proper boundary conditions over theplane of symmetry. For example, if the electric field is expected to be tangential to theplane of symmetry, be sure to use the boundary condition that forces the E-field to be tan-gential to the surface of the cylinder.







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Final Objects Must Not Overlap

In the final geometric model of a structure, object surfaces must not overlap. Objects canshare surfaces or edges or can be contained entirely within one another, but they cannothave overlapping surfaces.

• If one object partially overlaps another object, the geometry is invalid as the finalmodel. The system has no way of knowing which object occupies the shared volumeand problems will occur when the system attempts to create the finite element mesh.For example, above, the object on the right shows a sphere overlapping with a cube.

• If one object is completely inside another, there is no problem. The system can“subtract” the smaller object from the larger, and assume that the smaller objectoccupies the void in the larger object. For example, above, the structure to the leftshows a sphere entirely within the cube. This is valid because the sphere is assumedto occupy a void in the cube.

The restriction that the surfaces of objects must not overlap only holds for the final model.It is valid to create overlapping objects while building a geometry. When building complexobjects by uniting and subtracting simpler objects, creating objects that overlap arealmost always required.If two objects in the final model partially overlap, use the Solids/Subtract, Solids/Intersect, or Solids/Unite commands to subtract, intersect, or unite theoverlapping region of one of the objects.



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Sizing the Problem Region

The problem region is the region in which a field solution is to be generated. In general:

• No solution is computed outside the problem region.• The default size of the problem region is approximately equal to the size of a box that

encloses all objects.• All space inside the problem region that is not occupied by an object is considered to

be occupied by an object called background.

Before saving your final model, you can use the Options/Region command to change thesize of the problem region to something other than the default. You should consciouslydecide on the size of the problem region. If you accept the default values, be aware thatthe background object is approximately ten percent larger than the box that surroundsyour model.

Background

An object named background is automatically created by the system when the finalgeometry is saved. It occupies any portion of the problem region not occupied by objectsthat you have created. The background object can be displayed while the geometricmodel is being created. Material characteristics and boundary conditions can be assignedto it just as they can for any other object in the geometric model.

The background can occupy voids inside of objects. For example, if you subtract oneobject from another and then delete the smaller object, the resulting void is considered tobe part of the background.

Units

Choose the Options/Units command to define the modeling units. You may either of thefollowing metric or english units as the type of modeling units:

Regardless of the selected modeling unit, all solutions are given in SI units.

Metric km, meters, cm, mm, microns, nmEnglish yards, feet, inches, mils



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Level of Detail (Aspect Ratio)

In general, do not create geometries in which large dimensions and small dimensions dif-fer by more than three orders of magnitude. For example, do not create an object with oneside larger than 2 inches and another side smaller than 0.002 inches. Likewise, do notplace two objects with sides that are approximately 5 millimeters in length any closer than0.005 millimeters to one another. The system will be able to create a finite element meshfor geometries in which dimensions vary by more than three orders of magnitude, but itwill require much more time and memory to generate a solution.

If you wish to create such objects you may want to create virtual objects between theobjects so that a more appropriate mesh is generated.

Sizing Limits (Min D and Max D)

The 3D Modeler builds objects based on the concepts of Min D and Max D. These are theminimum and maximum sizes that an object can be. No object can be smaller than Min D,while no object can be greater than Max D.

Min D is defined to be the distance from a point to a line that is small enough for the pointto be considered resting on the line. Currently, Min D is assumed to be 10-7 times thesmallest dimension of the problem region. Do not create objects smaller than this amount.

Max D is defined to be the largest diagonal of the problem region. You will not be able tocreate an object exceeding the Max D.



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Virtual Objects

Virtual objects are dummy objects which are not needed in defining the geometry but areuseful in the meshmaking, solution, and analysis stages.

For example, if the dimensions of two objects differ by more than three orders of magni-tude, the simulator may not be able to accurately solve for fields in the structure. To pre-vent this, draw a virtual object between the two objects. This introduces more pointsbetween the objects to serve as tetrahedra vertices which improves the aspect ratio of themesh and makes the solution more accurate.

The conductor below has a radius of 0.0004 meters and is four meters from the outerboundary. Drawing a virtual object with a radius of 0.04 meters between these twoobjects, enables the system to generate a better finite element mesh and more accuratesolution for this structure.

However, be aware that this tactic will not work in all cases. Depending on the dimensionsof your geometry, your results may not be as expected.

Outer boundary

ConductorVirtual object

Radius = 0.0004 m

Radius = 4 m

Radius = 0.04 m



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Using 2D Objects as Thin Conductors and Resistors

In capacitance computations and electrostatic field simulations, 2D objects can be usedto model very thin conductors and resistors. As a general rule of thumb, use 2D objectswhen the thickness of the conductor or resistor is at least ten to twenty times smaller thanthe thickness of other objects in the geometry. This will make the solving time faster thanif it has to compute a three-dimensional object.

You can use thin 3D objects, but if the dimensions of the thin object are too small they cancause difficulties for the system when it attempts to create the finite element mesh.

Using 2D Objects as Coil Terminals

In magnetostatic and eddy current problems, you must specify the currents that give riseto magnetic fields.

• In conductors whose ends touch the edges of the solution region, you can specifycurrents and current densities via the Setup Boundaries/Sources command. You donot have to draw outer terminals in the current version of the Maxwell 3D.

• In conductors that lie entirely within the solution region and form a closed conductionpath, you must explicitly draw 2D objects to serve as “coil” or “branch” terminals. Thecurrent flow or voltage drop across the terminal is also defined via the SetupBoundaries/Sources command.

Any 2D objects that you wish to use as coil terminals must already be defined andincluded in the current geometry. These objects must also be an exact cross-section ofthe 3D conductor for which you wish to assign a terminal.

A coil terminal is a 2D object that exactly coincides with an inside cross-section of a 3Dobject, as shown below. It cannot be on a face of the 3D object; it must be a slice that cuts



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through the object.

Note that the current path above is a valid example of a coil terminal, since the objectscomprise a closed loop within the problem space.

Note: For magnetostatic and eddy current problems, when using symmetry a sym-metry plane that cuts through a coil, you must define two terminals if the coilis cut perpendicular to the current flow.

If the coil is cut parallel to the current flow, however, you may use only oneterminal (which will be half the size of the original terminal).



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Invalid Coil Terminals

Invalid coil terminals are shown below.

• Coil terminals only work for current loops that are entirely contained within the problemspace. The half coil above is part of a current loop that is not entirely contained withinthe solution region.

• Coil terminals only work for closed current paths. The bar on the right is not part of aclosed current loop. Current injected into it through the terminal has no way to returnto the other side of the terminal, and cannot flow outside of the object.

Warning: Although Maxwell 3D permits you to set up coil terminals in objects that donot have a closed current path, one of the following situations can occur:• The simulator may fail to compute a solution.• For magnetostatic problems, the initial conduction solution may fail to

converge.• The simulator may generate an inaccurate solution.



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Geometric Models forExecutive Parameters

Force and the GeometricModel

Torque and the Geomet-ric Model

Capacitance Matrices andthe Geometric Model

Inductance and the Geo-metric Model

Impedance and the Geo-metric Model



Geometric Models for Executive ParametersIf you plan to compute executive parameters such as force, torque, capacitance, induc-tance, or impedance, you may need to modify your model to suit the boundary conditions.

Force and the Geometric Model

The 3D Modeler computes virtual (electrostatic) or Lorentz (magnetostatic) forces byusing the principles of virtual work. You may wish to consult the theory and equationsbehind this process in the Technical Notes.

> To compute the force on your model:1. Choose Force under the Setup Executive Parameters option in the executive

commands menu.2. Choose Create to create a setup. A pop-up window appears.3. Enter the name of the setup.4. Highlight the names of the objects to include in the setup.5. Choose Yes to enter the objects into the setup.6. Choose File/Save from the menu bar.7. Choose Yes to save your changes.8. Choose File/Exit to return to the Executive Commands window.

Torque and the Geometric Model

The 3D Modeler computes virtual and Lorentz torques using both work principles andLorentz forces. You may wish to consult the theory in the Technical Notes.

> To calculate the torque on your model:1. Choose Torque under the Setup Executive Parameters option.2. Choose Create to create a setup. A pop-up window appears.3. Enter the name of the setup.4. Highlighting the names of the objects to include in the setup.5. Choose Yes to accept the object.6. Choose File/Save from the menu bar.7. Choose Yes to save your changes.8. Choose File/Exit to return to the Executive Commands window.



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Torque and the GeometricModel

Capacitance Matricesand the GeometricModel





Capacitance Matrices and the Geometric Model

The 3D Modeler computes capacitance from the results of a simulated electromagneticfield either in terms of charges and voltages or in terms of currents and time-varying volt-ages. Consult the Technical Notes for the equations and theory of calculating capaci-tance.

> To calculate the capacitance of your model:1. Choose Matrix under the Setup Executive Parameters option in the executive

commands menu.2. Highlight the names of the items you wish to include in the matrix.3. Choose Yes to accept the objects into the matrix. You can remove unwanted

objects by selecting them and choosing No.4. Choose File/Save from the menu bar.5. Choose Yes to save your changes.6. Choose File/Exit to return to the Executive Commands window.



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Inductance and the Geometric ModelClearly Define All Current Loops

To obtain precise inductance values, clearly indicate the current loop to which each con-ductor belongs when assigning your executive parameters. Current loops may be drawnin the geometry or defined through the use of symmetry. Terminals, boundary conditions,and current directions must be consistent with the current paths you’ve established.

If you are not careful when setting up the problem, the field simulator will not be able toidentify the loop to which each conductor belongs. To calculate inductance, it will assigneach conductor to a current loop of some sort — but not necessarily the one that youexpected. In the example shown below, the simulator will be unable to determine whetherthe conductors are part of two completely independent current loops, or the same currentloop. The simulator will assume that some type of current path exists and compute induc-tances for that loop. However, the current path that the field simulator comes up with maynot be the one you intended when setting up the problem. Thus, the inductance values itcomputes may not be physically meaningful for the problem you had in mind.

Current Direction

Current DirectionConductors

? ?

Which loop?

Current Direction



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Finding Inductance When No Loop Is Present

Occasionally, you may need to calculate inductance for a problem where current loopscannot be explicitly defined. For example, the return path for current may be outside of thedevice being modeled. In cases like this, calculate inductances by modeling the conduc-tors as though they are part of a current loop (even if no such loop exists in the actualstructure).

Approximate inductance values can be obtained through the use of symmetry. Forinstance, a row of pins in an integrated circuit package can be modeled as though eachpin is part of a complete current loop, as illustrated below. Only one pin is shown, thoughthe model would really include all pins in the row.

One problem with this model is that the inductance includes the effects of the 3D field thatexists in the entire loop, not just the row of pins. Additionally, the effect of other conductorson the pins’ inductance is not included. For instance, the conductors in the package’s leadframe are not included in the model, yet they could have a significant effect on the induc-tance of the package. To find inductances in this case, you would have to include theseconductors in the model.

Current Direction

Neumann BoundarySolutionRegion

Neumann Boundary

By setting up Neumann boundaries atthe ends of the pins, you can use sym-metry to define the current path foreach pin, as shown to the left. Theinductance is computed only for thepart of the loop that is actually modeledin the field simulator (that is, the singlerow of pins).



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Impedance and the Geometric Model

When drawing a model for which an eddy current field solution is to be computed, yourcurrent loops must be well defined. For details, see Inductance and the Geometric Model.

Skin Depth

In AC magnetic field simulations and impedance computations, induced currents allowmagnetic fields to penetrate conductors to a depth which is approximated by the formula:

where:

• ω is the angular frequency, which is equal to 2πf.• σ is the conductor’s conductivity.• µr is the conductor’s relative permeability.• µ0 is the permeability of free space.

Currents will be concentrated near the surface of the conductor, decaying rapidly past theskin depth. As the above relationship indicates, the skin depth gets smaller as the fre-quency increases.

To more accurately model the field patterns produced by induced currents, do one of thefollowing:

• If the skin depth is large compared to the conductor, refine the mesh inside the objectbetween the surface of the object and the skin depth (where you expect to find eddycurrents). Strategies for doing so can be found under Eddy Refinement.

• If the following conditions hold, use an impedance boundary to model the effect ofinduced currents on the behavior of the magnetic field at that surface:• The skin depth is very small compared to the dimensions of the problem.• The magnetic field decays faster inside the conductor than along the surface.• The current source is far from the surface where eddy currents occur, compared to

the size of the skin depth.

For more information on impedance boundaries, see Eddy Current Boundary Conditions.

δ 2ωσµ0µr

--------------------=



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Solution Analysis of Geo-metric Models


Solution Analysis of Geometric ModelsMaxwell 3D allows you to use the Setup Executive Parameters command to preparecalculations for the force, torque, and capacitance of your model.

Under Setup Solutions/Variables, a table of parameters lists all appropriate variablesand parameters pertinent to the model. If you have purchased the Parametric Analysismodule, this table can be modified so that you can then specify how many rows and col-umns you want and the range each parameter should have. For example, you can per-form a parametric analysis of your model by plotting how force varies with torque, or howtorque varies as the capacitance matrix changes. Later, you can save the fields, and ana-lyze the faces and fields of your model with these parameters in the Post Processor.



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Measuring DistancesBetween Objects

MacrosA macro is a recorded list of commands that you can execute to create a model. Whenyou execute this macro in any other project, the macro creates your model in the newproject.

You can access online help for a specific macro command by entering help command-name at the command prompt. This returns the full syntax of the command, includingdetails on each of the necessary arguments and their formats.

Creating a Macro

After you have started to record the macro, you can enter the script commands by eitherusing the mouse or entering the commands at the command prompt.

> To create a macro in the modeler:1. Choose View/Command Prompt from the modeler menu bar. The command

prompt window appears below the project window.2. At the command prompt, enter FileRecord Filename.mac where Filename.mac is

the name of the macro you wish to create. From this point forward, every step willbe recorded into the macro.

3. Create that part of your model that you wish to record. You can create this modelby using the mouse or by entering the commands into the command prompt. Thecommands that can be entered appear in the Introduction to the Ansoft MacroLanguage guide.

4. When you have finished creating the model you want to record, enter FileRecStop.Your macro is now finished and has been recorded.

Executing a Macro

You can execute the macro you have created in any project you wish. The macro will cre-ate the object with the settings saved in the macro.

> To execute a macro:1. Choose View/Command Prompt from the menu bar. The command prompt

window appears below the project window.2. At the command prompt, enter FileExec Filename.mac where Filename.mac is the

name of the macro you wish to execute.



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Editing a Macro

You can edit a macro with any text editor. You can also make changes to a macro andsave it under a different file name. This allows you to run several macros in sequence,each producing a slightly different object.

A Macro Example

Here is an example of a simple macro. This macro generates a straight line with a speci-fied number of segments:

FileRecord parmline.mac

Assign NAME Getstring “Enter polyline name”

ExpAssign “nseg” GetLong “Enter number of segments”

Assign STPOS GetPosition “Enter start position”

Assign ENDPOS GetPosition “Enter end position”

ExpAssign “x1” XComponent STPOS

ExpAssign “y1” YComponent STPOS

ExpAssign “z1” ZComponent STPOS

ExpAssign “x2” XComponent ENDPOS

ExpAssign “y2” YComponent ENDPOS

ExpAssign “z2” ZComponent ENDPOS

ExpEval “t=0”

ExpEval “x=x1 + t*(x2-x1)/nseg”

ExpEval “y=y1 + t*(y2-y1)/nseg”

ExpEval “z=z1 + t*(z2-z1)/nseg”

EditPline NAME

Repeat Add Eval “nseg” 1

AddVert3d ExpEval “X” ExpEval ”y” ExpEval “z”

ExpInc “t” 1

END

EndPline



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ReColor NAME 255 255 0

FileRecStop

To create the previous macro, you must type each line at the command prompt, thenchoose Enter to accept the command. When you have finished, this macro is savedunder the name Parmline.mac and can be executed in any project by typing:

FileExec Parmline.mac

at the command prompt.



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Script Instructions

Aside from script commands, three conditional script instructions also exist that can beentered at the command line.

IF

IF is used to create a conditional argument. For example:

IF EQ 2 2

ECHO “2 is equal to 2”

END...

Executing these commands will produce the echoed statement.

REPEAT

REPEAT is used to repeat a command. For example:

REPEAT 5

echo “Any instructions here”

END...

Executing these commands will repeat the echoed statement five times.

WHILE

WHILE is used to create a concurrent action. For example:

ASSIGN count 5

WHILE count

ASSIGN count SUB count 1

ECHO “count is “ count

END...

Executing these commands will display Count is 4, Count is 3, and so forth until thedecreasing value reaches zero. It stops at zero because the WHILE condition becomesfalse when the quantity reaches a negative value.



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Measuring Distances Between ObjectsEventually, you may need you measure the distance between the objects or the faces ofthe objects in your model. You will need to use the coordinates fields in the side window todetermine the distance between any two points.

> To measure the distance between two points, faces, or objects:1. Make sure that the coordinates type/unit menu in the side window is set to Abs for

absolute coordinates.2. Double-click on a point in the active view window or enter the coordinates of the

point in the coordinates fields in the side window. This point represents the initialpoint from which you will measure the distance.

3. Choose Rel from the coordinates type/unit menu in the side window. The Rad fieldchanges to the Dst field.

4. Double-click on a point in the active view window or enter the coordinates of thepoint in the coordinates fields in the side window. This point represents the finalpoint from which you will measure this distance.

The Dst field displays the distance between the two points.


Maxwell 3D — File MenuTopics:

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File MenuUse the File commands to perform the following tasks:

• Create new geometric models in the 3D Modeler.• Open existing model or solution files.• Close model or solution files.• Save models or solutions in disk files.• Record, save, execute, and delete macros.• Import a model or solution, replacing the one that’s currently loaded.• Export a model or solution to a different file format.• Define printer setups and print models.• Exit from the current software module.

When you choose File from the menu bar, a menu similar to the following one appears:

File MenuFile CommandsFile ExtensionsFile/NewFile/OpenFile/CloseFile/SaveFile/Save AsFile/MacroFile/ImportFile/ExportFile/Export AnimationFile/Print SetupFile/PrintFile/Apply ChangesFile/RevertFile/Exit



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File CommandsThe function of each File command is as follows.

Not all of these commands are available on the File menu of each software module.

Your model is not automatically saved. Therefore, be sure to frequently save your workwhile creating or editing a project. This prevents you from losing all of your changes if aproblem occurs that causes your workstation or PC to crash. If you made changes sincethe last time the model was saved, you are prompted to save when you close the projector exit the software.

New Opens a new window. New windows will close the windows of anyprevious models.

Open Reads in an existing geometric model or field solution. Opening anew window will close any currently open windows.

Close Closes the current model or solution, deleting the window it is dis-played in.

Save Writes out a model to a set of disk files.Save As Writes out a model under a different name.Macro Saves, records, executes, and deletes macros.Import Reads in geometric files. Also allows you to edit these files and save

the changes.Export Saves the current model or solution to a different file format.ExportAnimation

Post Processor. Exports an animated plot.

Print Setup Defines your print settings.Print Prints windows in the current project.Apply Changes Macro Editor. Applies the changes in the macro to the current model.Revert Meshmaker. Post Processor. Reverts the model to its original state.Exit Exits the current module and returns to the Executive Commands

window.



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File ExtensionsDifferent modules of Maxwell software save their files with different file extensions so thatyou and the software can tell which module created which file. For instance, the filenamed gear.sm2 is a 2D Modeler file. Some commonly used file extensions and theirassociated software modules are listed below.

.sm3 Geometric model files from the 3D Modeler. This module can beaccessed from:• Maxwell 3D version 4.1 or later.• Ansoft HFSS.• The Maxwell Q3D Extractor.

.sm2 Geometric model files from the 2D Modeler. This module can beaccessed from:• The 2D Modeler command in the Utilities panel.• The Maxwell 2D Extractor.• The Maxwell Planar Parameter Extractor• Maxwell 2D version 6.1 or later.• Ansoft Ensemble.2D modeler files can also be created in PlotData.

.obs, .att Geometric model files from Maxwell 2D’s Meshmaker module version4.33 or earlier.

.sld Geometric model files from the previous version of the 3D Modeler.This module can be accessed from:• Maxwell 3D version 4.1 or earlier.• The Maxwell 3D Parameter Extractor version 1.2 or earlier.• The Maxwell Quick 3D Parameter Extractor version 2.0 or

earlier.• Maxwell Eminence version 4.0 or earlier.These files can also be created in the current 3D Modeler.

.sol Solution files from Maxwell 3D.



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File/NewUse the File/New command to create a new, unnamed model or table. Any item createdin this window can be saved as a new project and is independent of any other model thatmay be loaded in the software. You specify the name of the new item when you save it, byusing the File/Save or File/Save As commands.

> To create a new project:1. Choose File/New. If your old model or table has not been saved, you will be

prompted to save it. If the item has been saved, the old one vanishes and awindow appears.

2. If you are creating a new model, select the units for the new model.3. Toggle the warning button, if desired. This allows you to turn off the drawing units

warning window. If the warning has been toggled off, no window appears.4. Choose OK to accept the units or choose Cancel to ignore the new window.5. Create your new model or table as you would normally.



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Read Only ModeOpening Maxwell 2DFiles version 4.33 (or ear-lier)

File/CloseFile/SaveFile/Save AsFile/MacroFile/ImportFile/ExportFile/Export AnimationFile/Print SetupFile/PrintFile/Apply ChangesFile/RevertFile/Exit

File/OpenUse this command to read in the following from a file:

• A geometric model. Objects can be copied from other models into the current project,but other models cannot be edited or saved as part of the current project.

• A field solution. The currently loaded solution is not deleted.• A parametric table. The currently loaded solution is not deleted.

On workstations, compressed files are automatically uncompressed when opened.

> To read in a file:1. Choose File/Open. A file browser appears.2. Use the file browser to find the file you wish to open. By default, files with the

acceptable file extensions for the software you are using appear in Filter bar.3. Select the file you wish to open:

• On a workstation, these files appear in the Files list box.• On a PC, these files appear next to the Directories box.The selected file is automatically listed.

4. Choose OK to complete the command.

The model then appears in the software.

Read Only Mode

In read-only mode, the system prevents you from saving any changes to the original file.However, you can use the File/Save As command to save the changes to a new file.



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Read Only ModeOpening Maxwell 2DFiles version 4.33 (orearlier)

File/CloseFile/SaveFile/Save AsFile/MacroFile/ImportFile/ExportFile/Export AnimationFile/Print SetupFile/PrintFile/Apply ChangesFile/RevertFile/Exit

Opening Maxwell 2D Files version 4.33 (or earlier)

In the 3D Modeler, the File/Open command is able to open geometry files created usingversion 4.33 (or earlier) of Maxwell 2D. This allows you to directly import these geometricmodels into the 3D Modeler, bypassing the Translators command on the Maxwell ControlPanel.

To open a file created with version 4.33 (or earlier) of Maxwell 2D, add an .obs or .attextension to the file name. The selected file will automatically be translated into the .sm2file format used by the 2D Modeler. The original file will not be modified unless youchoose to save the changes in .obs or .att format.

Only 2D geometric models may be read into the 3D Modeler (whether in the Utilities panelor another Maxwell software package). No mesh, material, boundary, or solution informa-tion can be translated or read from the 2D files.

File/CloseUse this command to close an open geometric model, executive command operation, orfield solution and its associated view window.

> To close a file:• Choose File/Close.

If the project has changed since the last time it was saved, you will be prompted whetheror not to save it to a disk file. Afterwards, the view window vanishes.



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File/SaveUse this command to save a geometric model, a set of boundary conditions, a materialassignment, any executive parameters, or a field solution to a file.

> To save to a file:• Choose File/Save. One of the following things happens:

• If the file has been saved before or you have specified a name for the project, thesystem saves the model to a disk file.

• If this is the first time the project is being saved and you have not yet specified aname for it, the menu shown under the description of the File/Save As commandappears. Follow the directions for this command to save the unnamed model forthe first time.

File/Save AsUse this command to save a geometric model or field solution under a different name.

> To save a file using the File/Save As command:1. Choose File/Save As. The Save Model window appears.2. Use the file browser to find the directory where you wish to save the file.3. Enter the name of the file to save in the Save file name field.4. Select Binary format to save the file in binary form. Leave it unselected to save

the file in ascii form.5. (3D Modeler only.) Select Verify model to verify the model before saving. This is

active by default. Optionally, leave this option deselected to save without verifyingthe model.

6. If the window has a Switch to saved field, do one of the following:• Leave the field selected to display the new file name, and close the current file.• Deselect Switch to saved to save the file under the new name without changing

which file is displayed.7. Choose OK or press Return.

Note: Be sure to save geometric models periodically; they are not saved automati-cally. Saving frequently helps prevent the loss of your work if a problemoccurs that causes your computer to crash.



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File MenuFile CommandsFile ExtensionsFile/NewFile/OpenFile/CloseFile/SaveFile/Save AsFile/Macro

File/Macro/Start Record-ing

File/Macro/Stop Record-ing

File/Macro/ExecuteFile/Macro/DeleteFile/Macro/PromoteFile/Macro/Edit Macro

File/ImportFile/ExportFile/Export AnimationFile/Print SetupFile/PrintFile/Apply ChangesFile/RevertFile/Exit

File/MacroChoose the File/Macro commands to perform the following tasks:

File/Macro/Start Recording

Choose this command to create a new macro and begin recording commands to it. Thecommands recorded in the macro may be entered thorough the command prompt win-dow, tool bar icons, or menu bar commands.

> To record a macro:1. Choose File/Macro/Start Recording. The Input macro name window appears.2. Enter the name of the macro. A .mac extension is automatically appended to the

filename.3. Choose OK to accept the name and begin recording the macro or Cancel to

cancel the creation of the macro.

The window closes and you may begin entering commands to record. Choose File/Macro/Stop Recording to end the macro.

Refer to Maxwell 3D’s Introduction to the Ansoft Macro Language for a complete list ofrecordable macro commands.

Start Recording Creates a new macro and begins recording commands to it.Stop Recording Stops recording script commands in the macro.Execute Executes the recorded macro.Delete Deletes an existing macro.Promote Copies a selected macro to a new directory.Edit Macro Accesses the macro editor.



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File/Macro/Stop Recording

Choose this command to stop recording the macro you are currently creating.

> To stop recording a macro:• Choose File/Macro/Stop Recording.

The macro stops recording. Recorded macros may be executed with the File/Macro/Exe-cute command.

File/Macro/Execute

Choose this command to execute recorded macros.

> To execute a macro:1. Choose File/Macro/Execute. The Execute macro file browser appears.2. Select the type of macro to execute:

• Project Macros lists the available project-related macros.• User Macros lists the more commonly-used macros.• Shared Macros lists the macros that are used in more than once location.• System Macros are located in the installation directory and list the commonly

used system macros.Once selected, the available macros appear.

3. use the browser to locate and select the macro (.mac) file to execute.4. Choose OK.

The macro is executed, performing each script command recorded in the macro file.



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File/Macro/Delete

Choose this command to delete any recorded macros.

> To delete a macro:1. Choose File/Macro/Delete. The Delete macro file browser appears.2. Select the type of macro file to delete:

• Project Macros lists the available project-related macros.• User Macros lists the more commonly-used macros.• Shared Macros lists the macros that are used in more than one location.• System Macros are located in the installation directory.Once selected, the available macros appear.

3. Select the macro (.mac) file to delete from the browser.4. Choose OK.

The selected macro is deleted.








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File/Macro/Promote

Choose this command to copy a selected macro file into a new directory. The followingmacro classifications are available:

> To promote a macro:1. Choose File/Macro/Promote. If no directory exists in which to promote the

macros, a window appears, asking you whether or not to create the directory.Choose Yes to create the directory. When the directory is in place, the PromoteMacro window appears:

2. Select the Selected Macro menu bar to define the type of macro to move. Oncedefined, a list of available macros appear in the left side of the window and theselected directory appears in the field below the list.

3. Select the Promote To menu bar to define the directory in which to store the newmacro. Once defined, the directory in which to store the macro appears in the fieldbelow the right side of the window.

4. Choose Promote to add the macro to the right side of the window.5. Choose Close to accept the settings and close the window.

Project Macros Project-related macros.User Macros The most common macros used in creating and completing a

project.Shared Macros Macros that can be used in more than one location.System Macros System-related macros.








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File/Macro/Edit Macro

Choose this command to edit an existing macro. You may need to specify the macro edi-tor to use in your preferences (.prefs) file prior to using this command. The preferencesfile is located in the /Maxwell/config directory.

To define the editor, add the following line to the end of your .prefs file:

MacroEditor EditorName macedit

where macedit is the executable name of the Ansoft Macro Editor.

> To edit a macro:1. Choose File/Macro/Edit Macro. The Ansoft Macro Editor appears.2. Modify the selected macro accordingly.3. When finished, choose File/Exit to exit the text editor.

You return to the Maxwell 3D Modeler.








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File/ImportUse these commands to read a geometric model or field solution directly into the currentwindow. The imported file replaces the existing model or solution in the view window andbehaves like any other model or solution.

The File/Import commands are as follow:

When importing an .sld file, any air regions that were created in the old model becomethe problem region in the new version. Likewise, any terminals created in the old modelare imported as sheet objects.

Like the File/Open command, this command can sometimes be used to bypass theTranslators command in the Maxwell Control Panel.

Compressed files are automatically uncompressed when they are opened.

File/Import/2D Modeler File

Use this command to import an .sm2 file created with the Maxwell 2D Modeler.

> To import a file in the 3D Modeler:1. Choose File/Import/2D Modeler File from the File menu.2. Use the file browser that appears to find the file you wish to open.3. Select the file you wish to import:

• On the workstation, these files appear in the Files list box.• On the PC, these files appear next to the Directories box.

4. Choose OK.

The file is imported, replacing the existing model.

2D Modeler File Imports a 2D modeler (.sm2) file.3D Modeler/ACIS Imports a 3D modeler (.sld or .sm3) file.Translate Imports a STEP, IGES, or ProEngineer model file.

File MenuFile CommandsFile ExtensionsFile/NewFile/OpenFile/CloseFile/SaveFile/Save AsFile/MacroFile/Import

File/Import/2D ModelerFile

File/Import/3D Modeler/ACIS File

File/Import/TranslateFile/ExportFile/Export AnimationFile/Print SetupFile/PrintFile/Apply ChangesFile/RevertFile/Exit



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File/Import/3D Modeler/ACIS File3D Modeler

Use this command to import an .sld file. When importing an .sld file, keep the followingpoints in mind:

• Any air regions that were created in the old model become the problem region in thenew version.

• Any terminals created in the old model are imported as sheet objects.• The imported file replaces the existing model in the view window and behaves like any

other model.• Like the File/Open command, this command can sometimes be used to bypass the

Translators command in the Maxwell Control Panel.• Compressed files are automatically uncompressed when they are opened.

> To import an .sld file in the 3D Modeler:1. Choose File/Import/3D Modeler/ACIS File from the File menu.2. Use the file browser that appears to find the file you wish to open.3. Select the file you wish to import:


4. Choose OK.

The file is imported, replacing the existing model.







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File/Import/Translate

Use this command to import a STEP, STP, IGES, or IGS model file into the Maxwell 3DModeler. Once imported, the software classifies the file based on the extension of the ini-tial file and invokes the appropriate translator. The translated file is then written to anACIS version 5.0 model file.

There is an automatic healing procedure is invoked after reading in the model. Thus, mostof the errors that could be corrected on translated models, like reversed face-normals,adjacent faces not matching correctly will be corrected. Currently, there are no user-defined tolerances or adjustments that can be done to help the automatic healing proce-dure. Some of the healing and translation functions are elaborate and time consuming. Sothe Abort button in the progress window may not respond quickly if you choose it.

A file named xlate.log is created in the project directory during the translation. This fileshows details about translation process and can be examined if the translation fails.

> To import a file:1. Choose File/Import/Translate. The M3D-Xlator window appears, along with the

Import 3D Model file browser.2. Select the .stp or .igs file to translate from the browser.3. Choose OK. The Translation in Progress window appears, scrolling text

information about the translation in progress. Choose Abort at any time during thetranslation to abort the process and return to the M3D-Xlator window.

The model can now be saved as an .sm3 file for use in the Maxwell 3D Modeler.

Scaling and Units Conversion

Once the model has been translated, verify that the units have been scaled correctly onimport. Choose Options/Units to change the units while keeping the same numerical val-ues, or to change the units while keeping the dimensions constant.

For example, if you have drawn a model in feet, that is two feet long, you can switch toinches such that the model is two inches long, or 24 inches long. If you find that the modeldoes not have proper dimension after the translation, you can rescale to match the dimen-sions or units of the original geometry.







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Design Intent and Planning

The design intent is the intention to do finite element analysis for electromagnetic analysismust be present at the time of drawing the geometry. It would be difficult and wasteful ofresources to try to solve geometries that were drawn completely ignoring the needs ofelectromagnetic analysis. However this does not mean the model must be drawn exclu-sively for computational electromagnetics.

Most CAD tools are user friendly and allow you, with very simple user directives, to main-tain multiple design intents on the same model. If the model is drawn systematically fromlarge features to small features, dimensioned properly, it would be a very simple matter tosuppress manufacturing details from a base model and generate a finite element model.

One of the simplest examples is the rounded corners on a box. If you draw (in ProEngi-neer or a similar feature-based modeler for manufacturing) a rectangle, extrude it andround a few edges, it would be trivial to suppress the corners to get a simpler model forFEA. On the other hand if you have drawn the rectangle, rounded a few corners, and thenextruded the shape, it would be very difficult to suppress the rounded corners.

Choose a tool that has sufficient accuracy to output models that will be correct, be awareof how it is drawn, and de-feature and simplify the model in the original CAD tool beforeexporting to STEP or IGES formats. This way, the analysis will be completely successful.

Note: Given a choice between STEP and IGES, choose STEP. It is more accurateand typically holds more information than IGES.







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STEP and IGES

The STEP and IGES file formats are industry standard file formats. Various vendorsimplement export to STEP and IGES with varying degrees of accuracy. The CAD vendorsserve many different segments of the market and so the geometry described by theseSTEP and IGES files vary greatly.

Some of the segments served by CAD vendors are:

• Design/visualization tools• Manufacturing• Production drawing/blueprinting• Prototyping• Driving numerically controlled milling machines.• Finite element stress, thermal or electromagnetic analysis.

The design philosophy of the original CAD tool influences the STEP and IGES files in var-ious ways. For example:

• Some of the models for visualizations are never intended to be manufactured. Theydo not form solids, but they all render quite successfully.

• Manufacturing tools pay great deal of attention to mounting brackets, steps, notches,screw holes etc. Many of these details are electrically insignificant. Many have surfacefeatures like embossed name of the model/manufacturer or a logo.

• Many tools that generate blueprints can allow some inaccuracies in drawing becauseit is usually read by those who can judiciously correct minor drawing mistakes.

• Tools that generate models to drive numerically controlled milling machines setup thetool path for the machines. Because it is not a fatal error for them if the tool path cutsnon-existing metal, (and is even sometimes desirable because this will reduce burringand similar actions), the model might not make a properly closed solid objects.

• Even if the CAD tool is designed for Finite Element Analysis, different fields havedifferent features that are significant. The fillets and rounds which are consideredirrelevant in thermal or electromagnetic analysis is crucial in stress analysisirrespective of the tool in which it was drawn.



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Batch Processing with the Translator

For batch processing you can invoke the new translator in the command line mode. Forexample to read in an IGES file named in.igs and to create an output file namedout.sm3, one can use the following command:

m3d_xlator -xlate -input_format iges -input in.igs -outputout.sm3

This is useful for translating a several files using a script or batch command.



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File MenuFile CommandsFile ExtensionsFile/NewFile/OpenFile/CloseFile/SaveFile/Save AsFile/MacroFile/ImportFile/Export

File/Export/2D ModelerFile/Export/Old 3DFile/Export/ACIS Ver 1.7File

File/Export/ACIS Ver 2.1File


File/Export AnimationFile/Print SetupFile/PrintFile/Apply ChangesFile/RevertFile/Exit

File/ExportUse these commands to write out a file in a 2D or 3D format.

The File/Export commands are as follow:

When you export a file in the 2D (.sm2) format, the xy plane is the one that is exported.

If you need to export an xy plane that is away from the origin, use the Coordinates/MoveOrigin command to redefine the location of the origin, then export the plane.

File/Export/2D Modeler File

Choose this command to export the model in .sm2 format.

> To export a file:1. Choose File/Export/2D Modeler FIle. A file browser appears.2. Use the browser to find the file you wish to open.3. Select the file you wish to export:


4. Choose OK.

The file is exported in the specified format.

2D Modeler File Exports the model file in .sm2 format.Old 3D Modeler (.sld) Exports the model file in the old 3D modeler (.sld) format.ACIS Ver 1.7 File (.sm3) Exports the model file in ACIS version 1.7 .sm3 format.ACIS Ver 2.1 File (.sm3) Exports the model file in ACIS version 2.1 .sm3 formatACIS Ver 3.0 File (.sm3) Exports the model file in ACIS version 3.0 .sm3 format



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File/Export/Old 3D Modeler

Choose this command to export the model in .sld model format used by older versions ofMaxwell 3D software.

> To export a file:1. Choose File/Export/Old 3D Modeler. A file browser appears.2. Use the browser to find the file you wish to open.3. Select the file you wish to export:


4. Choose OK.

The file is exported in the .sld format.

File/Export/ACIS Ver 1.7 File

Choose this command to export the model in an ACIS .sm3 model format used by olderversions of Maxwell 3D software.

> To export a file:1. Choose File/Export/ACIS Ver 1.7 File. A file browser appears.2. Use the browser to find the file you wish to open.3. Select the file you wish to export:


4. Choose OK.

The file is exported in the .sm3 format.



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4. Choose OK.






4. Choose OK.




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File/Export Animation3D Post Processor.

Choose this command to export an animation to a new file. Animations are typicallyexported using Cinepak with a compression of 50% by default.

> To export an animation:1. Create an animated plot in the 3D Post Processor.2. Choose File/Export Animation. The Export Animation window appears:

3. Select the animation to export from the Export animation pull-down menu.4. Enter the File name of the animation to export. Optionally, choose the file folder

icon to access a file browser and select the directory in which to store the file.5. Define the Format in which to export the animation. By default, GIF is the selected

format.6. Define the Size of the animation by doing one of the following:

• Select Use active window size (the default) to use the current window size as thesize of the animation.

• Select Specify size and enter the values for the Width and Height of theanimation window.



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7. Enter the Delay between frames. This value is entered in seconds, and uses avalue of 1 by default.

8. Optionally, select Gray scale to export the animation in gray scale. Gray scaleanimations tend to use less memory than full color animations.

9. Choose OK to export the animation or Cancel to cancel the action.



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File/Print SetupUse this command to define your printer settings such as the printer you wish to send theoutput to and the form and the orientation of the output. For workstations, this commandis identical to the Print command in the Maxwell Control Panel.

> To define the printer settings on a PC:1. Choose File/Print Setup. The Print Setup window appears.2. Select the Printer that you will send the output to.3. Select the Form of the output document.4. Select the Orientation of the output document.5. If the output is two-sided, select the type of output form you prefer.6. Specify any Maxwell options.7. Choose OK to accept the settings or choose Cancel to cancel the action.



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File MenuFile CommandsFile ExtensionsFile/NewFile/OpenFile/CloseFile/SaveFile/Save AsFile/MacroFile/ImportFile/ExportFile/Export AnimationFile/Print SetupFile/Print

File/Print/RectangleFile/Print/Active ViewFile/Print/Project


File/PrintUse the File/Print commands to print regions or windows of the screen. The followingcommands are available:

File/Print/Rectangle

Use this command to print a selected region of the window to a hardcopy.

> To print a region of the screen:1. Choose File/Print/Rectangle. The Print window appears.2. Select one of the following:

• Select File to print the selected region to a file. File formats are defined using theFile/Print Setup command.

• Select Printer and enter the name of the printer to which to send the hardcopy.3. Optionally, choose Print Setup to define the print settings. This command is

identical to the File/Print Setup command.4. Choose OK to accept the settings. The window closes, and the mouse cursor

changes to a hand icon.5. Click the left mouse button on the window from which to print. The cursor changes

to crosshairs.6. Click the left mouse button on one corner of the area to print.7. Click the left mouse button on the opposite corner to print.8. Repeat steps 6 and 7 for each region to print.9. Click the right mouse button to exit.

The selected regions are printed to the selected format.

Rectangle Prints only the selected region.Active View Prints the active view window.Project Prints all view windows in the current project.



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File MenuFile CommandsFile ExtensionsFile/NewFile/OpenFile/CloseFile/SaveFile/Save AsFile/MacroFile/ImportFile/ExportFile/Export AnimationFile/Print SetupFile/Print

File/Print/RectangleFile/Print/Active ViewFile/Print/Project


File/Print/Active View

Use this command to print only the active view window.

> To print the model in the active view window:1. Select the view window to print.2. Choose File/Print/Active View. The Print window appears.3. Select one of the following:



identical to the File/Print Setup command.5. Choose OK to accept the settings.

The active view window is then printed.

File/Print/Project

Use this command to print all current windows in the project.

> To print the project:1. Choose File/Print/Project. The Print window appears.2. Select one of the following:



identical to the File/Print Setup command.4. Choose OK to accept the settings.

The all view windows in the project are then printed.



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File/Apply ChangesMacro Editor

Use this command to apply the changes made to the current macro to the macro in theMacro Editor.

> To apply the changes:1. Modify the modeler macro as needed.2. Choose File/Apply Changes. The modifications are applied to the macro and the

model changes accordingly.

File/RevertMeshmaker

Use this command to undo your seed and mesh settings and revert back to the originalmeshing state of the object.

> To revert back to the standard mesh:• Choose File/Revert.

Your changes are undone. The mesh on the objects reverts to its original state.

File/ExitUse this command to exit the current software module.

> To exit the module:1. Choose File/Exit. The following message appears for each open project with

unsaved changes:

Save changes to “projectname” before closing?

where projectname represents the name of the selected project.2. Do one of the following:

• Choose Cancel to stay in the module and not save the changes.• Choose Yes to save the changes for the project before exiting.• Choose No to exit without saving the changes.

You then exit the current module and return to the Executive Commands window.


Maxwell 3D — Edit MenuTopics:

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Edit MenuEdit CommandsEdit/UndoEdit/RedoEdit/CutEdit/CopyEdit/PasteEdit/ClearEdit/UndeleteEdit/DuplicateEdit/SelectEdit/Select AllEdit/Deselect AllEdit/AttributesEdit/VisibilityEdit/Show AllEdit/Command HistoryEdit/Clear Bnd/SrcEdit/Reprioritize Bnd/SrcEdit/Select BodiesEdit/Deselect All BodiesEdit/Select FacesEdit/Deselect All FacesEdit/Insert RowEdit/Delete Row

Edit MenuUse the Edit commands to do the following:

• Undo or redo the last command.• Edit, undelete, select, or deselect rows of data, objects, or other items.• Duplicate objects along a line or around an axis, or mirror them about a plane.• Change the attributes and visibility of objects.

When you choose Edit from the menu bar, a menu similar to the following one appears:



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Edit CommandsUndo Reverses the effect of the last command.Redo Executes the last undone command again.Cut Deletes the selected items, placing them in the paste buffer.Copy Copies the selected items to the paste buffer.Paste Copies the contents of the paste buffer to the active project.Clear Deletes the selected items but does not place them in the paste buffer.Undelete Restores an item that has been removed with the Clear command.Duplicate Duplicates the selected items:

Along Line Along a straight line.Around Axis Around an axis.Mirror By mirroring them about a plane.

Select Select items to be edited.Select All 3D Modeler. Selects all items.Deselect All Deselects all currently selected objects.Attributes Change attributes of an item:Visibility Displays or hides objects.

Hide Selection Hides the selected objects.By Item Hides or makes visible selected objects.Toggle Region Toggles boundary region on/off.

Show All Displays all invisible objects.CommandHistory

Displays the command history of macro commands.

Clear Bound-ary/Source

Boundary/SourceManager.

Resets a surface to its default boundary conditions.

ReprioritizeBnd/Source

Boundary/SourceManager.

Defines the priority of a boundary or source on themodel.

Select BodiesMeshmaker. Selects objects for mesh refinement.Select Faces Meshmaker. Selects faces. Toggles with Deselect All Faces.Insert Row Param. Solutions Inserts a new row of data to a table.Delete Row Param. Solutions Deletes a row of data from a table.




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Edit/UndoUse this command to undo your last action. This is extremely useful for correcting mis-takes in sketches, but can be used to undo almost any action. You can redo the undonestep with the Edit/Redo command.

> To undo the last step:• Choose Edit/Undo.

Your last step is now undone.

Edit/RedoUse this command to redo the last step cancelled by the Edit/Undo command.

> To redo the step that you cancelled with Edit/Undo:• Choose Edit/Redo.

The step is redone.

Edit/CutUse this command to remove objects or rows of data from the view window and placethem in the paste buffer.

> To cut items from the active view window:1. Select the items by using one of the Edit/Select commands.2. Choose Edit/Cut. The items are removed from the screen and placed in the paste

buffer.

Items that have been cut may be pasted back into the active window using the Edit/Pastecommand. The items currently stored in the paste buffer are replaced by the next itemsthat are cut or copied into the buffer.




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Edit/CopyUse this command to copy the selected objects or rows of data into the paste buffer. Theselected items are not deleted.

> To copy items into the paste buffer:1. Select the items by using one of the Edit/Select commands.2. Choose Edit/Copy. The items are copied into the paste buffer.

Items that have been copied may be pasted into the active window using the Edit/Pastecommand. The items currently stored in the paste buffer are replaced by the next itemsthat are cut or copied.




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Edit/PasteUse this command to copy the contents of the paste buffer to the active window. Theitems in the paste buffer may be pasted back into the same window, or into a differentview window. Geometric objects may be copied into a different project as well as a differ-ent window. Any item in the paste buffer can be pasted repeatedly.

The Edit/Paste command only pastes the items that were placed in the paste buffer bythe most recent Edit/Cut or Edit/Copy command. Each time Edit/Cut or Edit/Copy ischosen, the buffer is overwritten with new items.

> To paste an item or group of items in the same project:1. Select the items to paste.2. Choose Edit/Cut or Edit/Copy to place the items in the paste buffer.3. Select the view window into which the items are to be pasted.4. Choose Edit/Paste. A rectangle outlining the location of the items from the paste

buffer appears on the screen to show you their location.5. Move the rectangle to the place where you want the items located and click the left

mouse button.

The pasted items then appear in the new location.

> To paste an object to a different project:1. Select the items to paste.2. Choose Edit/Cut or Edit/Copy to place the object in the paste buffer.3. Open the new project that you wish to place the object in. The current project

closes automatically.4. Choose Coordinates/Set Object CS to set the coordinate system.5. Select an anchor point in the view windows. This marks where your object will be

pasted.6. Choose Edit/Paste to paste the object in its new location.

The object appears in its new location.




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Edit/ClearUse this command to delete all the selected items. The deleted items are not stored in thepaste buffer.

> To clear items:1. Select the items by using one of the Edit/Select commands.2. Choose Edit/Clear.

The selected items are deleted from the screen.

Edit/UndeleteUse this command to undelete an object that you have deleted with the Edit/Clear com-mand.

> To restore a previously deleted object to your model:1. Choose any view window.2. Choose Edit/Undelete.

The last item to be deleted reappears.

Edit/DuplicateUse these commands to make copies of objects in the active window. These commandscombine the functions of the Edit/Copy and Edit/Paste commands, copying the selecteditems and pasting them the number of times you specify. They are:

Before duplicating an item, you must first select it by clicking on it or by using one of thecommands from the Edit/Select menu.

The Edit/Duplicate commands can only be used to copy items within a project. To copyitems to another project, use the Edit/Cut and Edit/Paste commands.

Along Line Duplicates the selected item along a straight line.Around Axis Duplicates the selected item and revolves the copies of it

around an axis.Mirror Duplicates the selected item and mirrors it about a plane.




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Edit/Duplicate/Along Line

Use this command to copy the selected objects along a straight line. The line along whichthe items are duplicated can be vertical, horizontal, or lie at an angle.

> To duplicate items along a line:1. Select the items by using one of the Edit/Select commands.2. Choose Edit/Duplicate/Along Line.3. Select an anchor point for the items to be duplicated. This point is used to align the

duplicated objects along the line. Any point in the drawing space can be selected;however, selecting an anchor point on an item’s edge or within the item makes iteasier to select the duplication line. The coordinates of this point are nowdisplayed under the Enter Vector field. Choose Reset Start to select a new pointif you misplace the original point. Alternatively, you can use the keyboard to enterthe coordinates of this vector in the Enter Vector fields.

4. Enter the length of the vector in the Vector length field.5. Choose Enter to accept the vector or choose Cancel to cancel the action.6. Enter the number of copies to be made in the Total Number field. The number of

copies that you specify includes the original copied object.7. Choose Enter or press Return.

The system then copies the items, spacing them along the line according to the point youselected.




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Edit/Duplicate/Around Axis

Use this command to copy the selected objects and revolve them around an axis. Youmay duplicate items around the predefined x-, y-, and z-axes, or a specified axis of yourown.

> To duplicate items around an axis:1. Select the items by using one of the Edit/Select commands.2. Choose Edit/Duplicate/Around Axis. New fields appear in the side window.3. Select the axis around which you wish to duplicate the object.4. Enter the angle between each duplicate in the Angle field.

• A positive angle causes the item to be copied in the counter-clockwise direction.• A negative angle causes the item to be copied in the clockwise direction.

5. Enter the number of copies to be made in the Total Number field. The number ofcopies that you specify includes the original copied object.

6. Choose Enter to accept the duplicate or choose Cancel to cancel the duplicates.

The system copies the selected items, spacing each duplicate along the axis at the angleyou specified. For example, the rectangle on the following page was copied three times,each copy at an angle of 90 degrees. Note that the duplicates of the object are selected.




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When you copy an object, the original object remains in its position.



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Edit/Duplicate/Mirror

Use this command to mirror and copy the selected objects about a plane. This commandis similar to the Arrange/Mirror command, except that it copies the selected itemsinstead of moving them.

> To mirror and duplicate items about a plane:1. Select the items by using one of the Edit/Select commands.2. Choose Edit/Duplicate/Mirror.3. Select the first point on the plane. You may use the keyboard to enter the point’s

coordinates in the coordinates fields.4. Choose Enter to accept this point or choose Cancel to cancel the action.5. Select the point on the normal plane. (Again, you may enter the point from the

keyboard.)6. Choose Enter to accept this point or choose Cancel to cancel the duplicate.

A mirror-image copy of the selected items appears on the screen. In this case, the rectan-gle in the positive xy-plane was duplicated around the y-axis. Note that the duplicatedrectangle is highlighted, not the original one.



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Edit/SelectUse these commands to select items to be edited. This command can also be accessedby clicking the right mouse button and choosing Select from the menu that appears.

You must select an item or group of items with one of the Edit/Select commands beforeentering the commands in the tables below. Selecting identifies the objects and text onwhich those commands act. The following commands require a selection:

> To select objects using the Edit/Select command:1. Choose Edit/Select. A list of objects appears on the right of the window.2. Select an object in one of the following ways:

• On workstations, choose the name of the object you want to select. The object’scolor changes to purple. On PCs, hold Ctrl to prevent deselecting other objectswhile selecting the new item.

• Click on the object itself with the mouse. When selecting faces of objects with themouse, if you click on an edge, a face adjacent to this edge will be selected. Clickagain on the same edge, and the next adjacent face becomes selected. When youcontinue to click on the edge, the faces are selected and deselected in a circularmanner. This allows you to select faces that are normally hidden behind otherfaces.

• Enter the name (with wildcards, if necessary) in the edit box below the list box.

Edit Menu Arrange Menu

Cut Move

Copy Rotate

Clear Mirror

Duplicate (all subcommands) Scale

Deselect All

Visibility/Hide Selection



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In modules other than the 3D Modeler, use the Edit/Select commands to select items:

Edit/Select/By Name

3D Boundary/Source Manager

Use this command to select items by name.

> To select objects by name:1. Choose Edit/Select/By Name. A pop-up window appears.2. Select an Object, Boundary, or Face.3. Select the object by either highlighting the object’s name or entering the object’s

name, and choosing OK. Use wild cards to select multiple objects.4. Choose Done to select the highlighted objects.

Edit/Select/By Volume


Use this command to select objects that lie completely within a volume box.

> To create a volume box:1. Choose Edit/Select/By Volume.2. Select a point in the window. This marks the box base vertex.3. Enter the dimensions of the box in the coordinates fields.4. Choose Enter to accept the values or choose Cancel to cancel the action.

The objects within the box are highlighted. The box itself vanishes.

By Name 3D Boundary/SourceManager

Selects objects, boundaries, and faces by name.

By Volume 3D Boundary/SourceManager

Selects the objects that lie inside a box that youspecify.

FacesIntersection

3D Boundary/SourceManager

Selects the intersecting faces of two 3D objects.



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Edit/Select/Faces Intersection


Use this command to select the intersecting surfaces of two 3D objects.

> To select intersecting surfaces:1. Choose Edit/Select/Faces Intersection. A list of objects in the model appears.2. Select the two objects whose surfaces touch.3. Choose Pick Intersection. The intersecting surfaces of the objects are selected.4. Repeat steps 2 and 3 to select additional intersecting surfaces.5. Choose Done when you are finished.

Edit/Select All3D Modeler

Use this command to select all the objects in the view windows. This is particularly usefulfor copying the entire model (When used in conjunction with the Edit/Copy command) ordeleting the objects of the model (when used in conjunction with the Edit/Clear com-mand).

> To select all the items in the view windows:• Choose Edit/Select All.

All items in the viewing windows are selected.



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Edit/Deselect AllUse this command to deselect any items that are currently selected and highlighted.

> To deselect all selected items:• Choose Edit/Deselect All.

All previously selected items are now deselected and no longer highlighted.

Deselecting Items With the Mouse> To deselect individual items with the mouse:

1. Click and hold the right mouse button to obtain the right mouse button menu.2. Choose Deselect All.

All previously selected items are now deselected and no longer highlighted.

Edit/AttributesThe commands in the Edit/Attributes menu are:

These attributes are set on an item-by-item basis.

Edit/Attributes/By Clicking

Use this command to modify object and text attributes one item at a time. The followingattributes may be changed:

• The name and color of a geometric object.• The visibility of the object.• Whether an object is used in the model from which a solution is generated.• The display of the object as wireframe or shaded.• Whether the orientation of the object is shown.

Clicking on the objects themselves is typically the most useful way to select them.

By Clicking Change various object attributes, including names, visibility, color,shading, and orientation.

Recolor Change the color of the selected items.



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> To change the attributes of an object:1. Choose Edit/Attributes/By Clicking. A list of objects appears in the side window.2. Select the object whose attributes you wish to change.3. Choose OK. The Object Attributes window appears.4. Change the attributes you wish to modify.5. Choose OK or press Return. The object’s attributes are changed. To leave an

object’s attributes completely unchanged, choose Cancel from the ObjectAttributes window.

6. Choose Cancel from the side window to exit the command.

When you select an object using the Edit/Attributes/By Clicking command, the followingwindow appears.

The following object attributes may be modified.



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Color

Controls the object’s color.

> To change the color:1. Click on the box beside the Color field. A palette of colors appears.2. Select the new color. The color of the object is changed to the color you selected.

Name

Specifies the name of the object.

> To change the name:1. Click the left mouse button on the Name field.2. Enter the new name for the object.

Names can be up to 15 characters long. They may only include alphanumeric characters(a-z, A-Z, and 0-9) and underscores (_). You cannot assign the same name to more thanone object. The name background is reserved for use by the system and cannot beassigned to an object.

Show Orientation

Determines whether the object’s orientation is displayed.

> To show the object’s orientation:1. Choose Show Orientation. A list of the objects in the active window appears.2. Select the name of the objects whose orientations you wish to display.3. Choose OK to accept the object or choose Cancel to ignore the action.

The object’s orientation appears. Arrows mark the directions of the axes.



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Model

Determines whether the object is used in the final geometric model — that is, whethermaterial properties and boundary conditions are defined and a finite element mesh gen-erated for the object. By default, all objects are model objects.

No materials or boundary conditions can be specified for “non-model” objects. Theseobjects are saved with the rest of the geometry and remain a part of the geometric model,even though they are not used in generating a solution.

> To toggle between “model” and “non-model” status for an object:• Select Model.

Display as Wireframe

This option determines the shading of the object. If the Display as Wireframe button isactive, the objects in the selected window appear in wireframe. If the button is inactive, theobjects are shaded in the active view window.

> To toggle between wireframe and shaded status for an object:• Select Display as Wireframe.

Displaying an object in wireframe is useful when your model contains an object that restsinside another. This allows you to see both objects simultaneously. Shading objects isbest used when your model has two or more different objects occupying separate spaces.This allows you to see the objects in their full sizes.

As a general rule, set a wireframe display on thin or 2D objects. Set a shaded display on3D objects. This is conceptually easier to imagine.



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Edit/Attributes/Recolor

Use this command to change the color of the selected objects. You may select any colorthat is part of the user color palette in the Color Manager. Recoloring objects may allowyou to easily differentiate between modeled objects on the screen.

> To change the color of the selected items:1. Select the items by using the Edit/Select command.2. Choose Edit/Attributes/Recolor. A pop-up window appears, displaying the

current default drawing color in a square in the Color field.3. Click on the colored square. A palette of colors appears.4. Select the new color for the object.5. Select the Make it the default color to assign the color as the default. This is the

default setting.6. Select the Recolor Selection to recolor the selected objects. This is the default

setting.7. Choose OK to accept the recolor or choose Cancel to cancel the recoloring.

The object and text colors change to the new settings.



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Edit/VisibilityUse the following Edit/Visibility commands to hide or display items:

Edit/Visibility/Hide Selection

Use this command to hide an object. Hidden objects that are defined as model objects willbe included in the final model, but will not be visible.

> To hide an object:1. Select the object to hide with one of the Edit/Select commands.2. Choose Edit/Visibility/Hide Selection.

The selected objects and text are hidden. To redisplay all objects, use the Edit/Show Allcommand.

Edit/Visibility/By Item

Use this command to either hide or display items.

> To hide or display items:1. Choose Edit/Visibility/By Item. A menu appears with the names of all the objects

in your model.2. To change the visibility status of an object, click the left mouse button on it to

highlight it. Do one of the following:• To hide an object, set it to No.• To display an object, set it to Yes.

3. Choose OK when you are finished changing the settings.

Objects are then hidden or displayed accordingly. To redisplay all objects, use the Edit/Show All command.

Hide Selection All modules Hides selected objects.By Item All modules Specify, object by object, whether

to display objects.Toggle Region Boundary/Source Manager,

Setup Executive Parameters.Toggles the modeling region onand off.



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Edit/Visibility/Toggle Region

Use this command to toggle the boundary region on or off. This does not affect the modelitself.

> To toggle the boundary region:• Choose Edit/Visibility/Toggle Region.

The region toggles on and off.

Edit/Show AllUse this command to display all items that have been made invisible with one of the Edit/Visibility commands.

> To display all invisible items:• Choose Edit/Show All.

All items are now visible.



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Edit/Command HistoryAnsoft Macro Editor

Use this command to display the list of commands you have just executed in the form of amacro. Once the macro is displayed in the Ansoft Macro Editor, it can be modified andsaved.

When the model is saved in the Maxwell 3D Modeler as an .sm3 file, the macro is savedin mod3/projname.mac. When the .sm3 file is read, its corresponding macro file is alsoread.

Some geometries can be visualized, including boxes, cylinders, rectangles, circles, arcs,and points. When you select the line in the macro editor, the geometry is highlighted in theMaxwell 3D Modeler, and as you change the parameters of the command, you can pre-view it in the modeler.

> To save the commands as a macro:1. Create the model using the Maxwell 3D Modeler.2. Choose Edit/Command History. The Ansoft Macro Editor appears.3. Use the Ansoft Macro Editor to modify the list of commands, or any values

associated with them.4. Optionally, choose File/Apply Changes to immediately apply changes made to

the model. This allows you to make corrections without the need to exit the MacroEditor.

5. Choose File/Save to save any changes to the macro.6. Choose File/Exit to return to the Maxwell 3D Modeler.

Note: To access this command and receive these features, choose Edit/Com-mand History instead of File/Macro/Edit Macro. Accessing the Macro Edi-tor directly from the software will not provide access to this command.



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Edit/Clear Boundary/SourceBoundary/Source Manager

Use this command to reset the selected surfaces to their default boundary conditions,deleting any boundaries or sources that you may have set.

• Boundaries between objects are reset to Natural boundaries.• Outside boundaries are reset to Neumann boundaries.

> To clear a condition:1. Select the object whose boundary conditions you want to clear.2. Choose Edit/Clear Boundary/Source.

Use the Edit/Undo Clear command to restore a boundary or source cleared with theEdit/Clear Boundary/Source command.



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Edit/Reprioritize Boundary/Source3D Boundary/Source Manager

Use this command to change the position of the selected boundary in the Boundary list.The order the boundaries appear in the Boundary list indicates the order in which theywere defined. The boundaries at the top of the list were defined first, while the boundariesat the bottom were defined last. The order in which the boundaries are defined is criticalwhen two boundaries overlap.

> To change the order of the boundaries:1. Select the object whose order you want to change.2. Choose Edit/Reprioritize Boundary/Source. The boundary moves down one

spot in the Boundary list.

Edit/Select BodiesMeshmaker

Use this command to select the objects that you want to manually seed. This commandtoggles with the Edit/Deselect All Bodies command.

> To select a body to manually mesh:1. Choose Edit/Select Bodies. A list of objects appears.2. Select the objects you want to manually mesh.3. Choose OK.

Edit/Deselect All BodiesMeshmaker

Use this command to deselect all of the selected bodies that you are manually seeding.

> To deselect the objects:• Choose Edit/Deselect All Bodies.

All the objects are now deselected.



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Edit/Select FacesMeshmaker

Use this command to select the faces that you want to manually seed. This command tog-gles with Edit/Deselect All Faces.

> To select a face to manually seed:1. Choose Edit/Select Faces. A list of faces appears.2. Select the name of the face you wish to manually seed.3. Choose OK.

The selected faces can now be manually seeded.

Edit/Deselect All FacesMeshmaker

Use this command to deselect all the faces you selected with the Edit/Select Faces com-mand.

> To deselect all the faces:• Choose Edit/Deselect All Faces.

All the faces are deselected.

Edit/Insert RowParametric Solution Options

Use this command to insert rows of data into your table.

> To insert a row in your data table:• Choose Edit/Insert Row.

The name for the new row of data appears under the Setup column.



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Edit/Delete RowParametric Solution Options

Use this command to delete unwanted rows of data from your data table. This will hastenthe solving process.

> To delete rows of data from your table:1. Choose Setup from the data table.2. Choose Edit/Delete Row.

The tables are now deleted.


Maxwell 3D — View MenuTopics:

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View MenuView CommandsUsing the Mouse to Changethe View

View/RenderView/Zoom InView/Zoom OutView/Fit SelectionView/Fit AllView/Reset Standard ViewsView/OrientationsView/Coordinate SystemView/Grid PlaneView/Setup GridView/Side WindowView/ToolbarView/Command PromptView/Status BarView/Save Module Prefer-ences

View/Revert to DefaultsView/Toggle Boundary Visu-alization

View MenuUse the commands on the View menu to:

• Display wire frame, flat shaded, or smooth shaded views of objects.• Set defaults for displaying the geometric model, its coordinate system, and grid.• Specify the location of the tool bar, command prompt, and status bar.

When you choose the View menu, a menu similar to the following one appears:



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View CommandsThe commands on the View menu are:

Using the Mouse to Change the ViewAs an alternative to using the commands on the View menu, you can use the pop-up win-dow given by pressing the right mouse button. Choose Pan, Zoom, or Rotate from themenu. Choose Position to return to normal viewing.

You can also Pan, Zoom, or Rotate without the right mouse button menu. You can usethe mouse in conjunction with the keyboard to change the view of the model such as withhotkeys.

Render Displays the objects in the geometric model with wire outlines,flat shaded surfaces, or smoothed, shaded surfaces.

Zoom In Zooms in on an area of the geometry, magnifying the view.Zoom Out Zooms out of an area of the geometry, shrinking the view.Fit Selection Changes the view to display all items that are selected.Fit All Changes the view to display all objects in the model.Reset Standard Views Returns all view windows to the standard views.Orientations Defines the orientation of the model axes.Coordinate System Controls how the model’s coordinate axes are displayed.Grid Plane Changes the display of the xy, yz, and xz grid planes.Setup Grid Sets the grid spacing and other grid settings.Side Window Sets the side window to the left or right of the view windows.Tool Bar Specifies the location and display of the tool bar.Command Prompt Accesses the command prompt, allowing you to enter scripts.Status Bar Controls whether the status bar is displayed.Save ModulePreferences

Saves your current module settings and preferences.

Revert to Defaults Reverts all settings back to the original defaults.Toggle BoundaryVisualization

Boundary/Source Manager. Toggles the boundary on or off.

View MenuView CommandsUsing the Mouse toChange the View





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View/RenderUse these commands to change how the objects in the geometric model appear. You candisplay them with:

The type of rendering you select applies only to the active view window.

View/Render/Wireframe

Use this command to view only the skeletal structure of the objects in the active window.This allows you to see all sides of the object at the same time.

> To make your sketch a wire framed model:1. Select the window in which you want to view the objects as wire frame.2. Choose View/Render/Wireframe.

A wire frame display of a geometry is shown below:

Wireframe Wire frame outlines (the default).Flat Shaded Flat, shaded surfaces.Smooth Shaded Smoothed, shaded surfaces.






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View/Render/Flat Shaded

Use this command to shade in the solid regions of an object in flat shaded mode. In thismode, the entire object is subdivided into planar polygons. Each polygon is shaded in thesame color. Only the active view window is affected by this command.

> To render your objects in flat-shaded mode:1. Select the window that you wish to view the shaded objects.2. Choose View/Render/Shaded Flat.

A shaded flat display of a geometry is shown below:






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View/Render/Smooth Shaded

Use this command to shade in the solid regions of an object in smooth shaded mode. Inthis mode, the entire object is subdivided into planar polygons. The shading varies acrosseach polygon to give the impression of a smooth surface. Only the active view window isaffected by this command.

> To render your objects in smooth-shaded mode:1. Select the view window that you wish to view the shaded objects.2. Choose View/Render/Smooth Shaded.

A shaded, smooth display of a geometry is shown below:






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View/Zoom InUse this command to zoom in on a region of the active view window, magnifying the view.

> To zoom in on the view window:1. Choose View/Zoom In.2. Select a point at one corner of the region that is to be zoomed in one of the

following ways:• Click the left mouse button on the point.• Enter coordinates of the point in the coordinates fields.

3. Select a point in the diagonal corner, using either the mouse or the keyboard.

The system then expands the selected region to fill the window.

Zooming In With the Mouse

As an alternative to using the View/Zoom In command, use the mouse to zoom in towardthe geometric model.

> To zoom in using the mouse:1. Click the right mouse button. A pop-up menu appears.2. Select Zoom from the menu. A small magnifying glass icon appears.3. Click and hold the magnifying glass icon at the center of the screen that you want

to zoom in on.4. Move the icon towards the top of the screen. As your move the icon, you will be

zooming in toward the object.






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View/Zoom OutUse this command to zoom out on the field of view in the active view window, shrinkingthe view.

> To zoom out and shrink the view:1. Choose View/Zoom Out.2. Select a point at one corner of the region that is to be zoomed in one of the

following ways:• Click the left mouse button on the point.• Enter coordinates of the point in the coordinates fields.

3. Choose the point in the diagonal corner, using either the mouse or the keyboard.

The system then redraws the screen, changing the current view to fit in the selected area.

Zooming Out With the Mouse

As an alternative to using the View/Zoom Out command, use the mouse to zoom out ofthe geometric model.

> To zoom out using the mouse:1. Click and hold the right mouse button to obtain the menu. A pop-up menu appears.2. Select Zoom from the menu. A magnifying glass icon appears.3. Click and hold the magnifying glass icon at the center of the screen that you want

to zoom out from.4. Move the icon towards the bottom of the screen. As your move the icon, you will be

zooming out away from the object.






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View/Fit SelectionUse this command to display all selected items in the active view window. This commandallows you to see all selected items at the same time.

> To fit all the selected items in the active view window:1. Select a view window as the active one.2. Choose View/Fit Selection.

The view in the active viewing window changes to include all items in the model that havebeen selected by clicking or by one of the commands on the Edit/Select menu.

View/Fit AllUse these commands to display the entire geometric model in the active view windowEach model is redrawn in the windows to allow the entire model to fit within it based onthe type of command:

View/Fit All/All Views

Choose this command to fit the entire model in all viewing windows.

View/Fit All/Active View

Choose this command to view the entire model and the modeling region in one view win-dow.

> To fit all the objects in the active window:1. Select a view window as the active one.2. Choose View/Fit All.

The view in the active viewing window expands to include all items in the model. The sizeof the window does not change.

All Views Displays the entire model in each of the view windows.Active View Displays the entire model in the active view window.






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View/RenderView/Zoom InView/Zoom OutView/Fit SelectionView/Fit AllView/Reset StandardViews

View/OrientationsView/Coordinate SystemView/Grid PlaneView/Setup GridView/Side WindowView/ToolbarView/Command PromptView/Status BarView/Save Module Prefer-ences


View/Reset Standard ViewsUse this command to return all viewing windows in the 3D Modeler to their standard dis-plays. This command removes all shading, zooming, and panning effects that may havealtered the display of the model.

> To reset the viewing windows to their defaults:• Choose View/Reset Standard Views.

All view windows are reset to their standard displays.

View/OrientationsUse this command to define and display a new orientation for the 3D model.

> To create a new orientation:1. Choose View/Orientations. The Edit View Orientation window appears.2. Choose Create. The Create New Orientation window appears.3. Enter the Name of the new view orientation.4. Do one of the following:

• Enter the Theta and Phi angles of orientation. Angles are entered in degrees.• Choose Use Current View Orientation to use the currently defined orientation as

the named orientation.5. Choose OK to accept the orientation.6. Choose Close to return to the 3D Modeler.

> To use a defined orientation for the display of the model:1. Choose View/Orientations. The Edit View Orientation window appears.2. Select the orientation to use from the Orientations list.3. Choose Set.

The model is redrawn in each view window with the selected orientation.



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View/Coordinate SystemUse these commands to do the following:

These commands operate on the active view window.

View/Coordinate System/Show

Use this command to display the x-, y-, and z-axes of the model’s coordinate system (thedefault). It toggles with View/Coordinate System/Hide.

> To display the axes:1. Select a window as the active one.2. Choose View/Coordinate System/Show.

View/Coordinate System/Hide

Use this command to hide the x-, y-, and z-axes of the model’s coordinate system. It tog-gles with View/Coordinate System/Show.

> To hide the axes:1. Select a window as the active one.2. Choose View/Coordinate System/Hide.

Show Shows the x-, y-, and z-axes (the default). Toggles with View/Coor-dinate System/Hide.

Hide Hides the x-, y-, and z-axes. Toggles with View/Coordinate Sys-tem/Show.

Large Displays the x-, y-, and z-axes as extending to the edges of theview window (the default). Toggles with View/Coordinate System/Small.

Small Displays the x-, y-, and z-axes in a smaller size. Toggles with View/Coordinate System/Large.

Positive Only Displays only the positive x-, y-, and z-axes (the default). Toggleswith View/Coordinate System/Both Sides.

Two Sided Displays both the positive and negative x-, y-, and z-axes. Toggleswith View/Coordinate System/Positive Only.



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View/Coordinate System/Large

Use this command to display the x-, y-, and z-axes in a size that extends to the edges ofthe view window (the default). It toggles with View/Coordinate System/Small.

> To make the axes fill the window:1. Select a window as the active one.2. Choose View/Coordinate System/Large.

View/Coordinate System/Small

Use this command to display the x-, y-, and z-axes in a smaller size that lies entirely withinthe active view window. It toggles with View/Coordinate System/Large.

> To make the axes fit entirely within the window:1. Select a window as the active one.2. Choose View/Coordinate System/Small.

View/Coordinate System/Positive Only

Use this command to display the positive x-, y-, and z-axes (the default). It toggles withView/Coordinate System/Two Sided.

> To view only the positively valued axes:1. Select a window as the active one.2. Choose View/Coordinate System/Positive Only.

View/Coordinate System/Two Sided

Use this command to display the positive and negative x-, y-, and z-axes. It toggles withView/Coordinate System/Positive Only.

> To view both sets of axes:1. Select a window as the active one.2. Choose View/Coordinate System/Two Sided.



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View/Grid PlaneUse these commands to do the following:

These commands operate on the active view window.

View/Grid Plane/Show

Use this command to display the grid plane (the default). It toggles with View/Grid Plane/Hide.

> To view the grid plane:1. Select a window as the active one.2. Choose View/Grid Plane/Show.

View/Grid Plane/Hide

Use this command to hide the grid plane. It toggles with View/Grid Plane/Show.

> To conceal the grid plane:1. Select a window as the active one.2. Choose View/Grid Plane/Hide.

Show Displays the grid plane (the default). Toggles with View/Grid Plane/Hide.

Hide Hides the grid plane. Toggles with View/Grid Plane/Show.XY Displays the grid in the xy-plane (the default).YZ Displays the grid in the yz-plane.XZ Displays the grid in the xz-plane.

Note: The View/Grid Plane commands only control the location and display of thegrid. Other grid settings — such as the grid spacing and the type of grid —can be specified using the View/Setup Grid command.



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View/Grid Plane/XY

Use this command to display the active window’s grid in the xy-plane (the default).

> To view the XY-plane:1. Select a window as the active one.2. Choose View/Grid Plane/XY.

View/Grid Plane/YZ

Use this command to display the active window’s grid in the yz-plane. This is the defaultsetting.

> To view the YZ-plane:1. Select a window as the active one.2. Choose View/Grid Plane/YZ.

View/Grid Plane/XZ

Use this command to display the active window’s grid in the xz-plane.

> To view the XZ-plane:1. Select a window as the active one.2. Choose View/Grid Plane/XZ.



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View/Setup GridUse this command to change the following grid settings:

• Auto Adjust Density• Cartesian• Polar• Suggested Spacing• Grid Visibility

This command operates on the grid in the active view window.

> To set the grid settings:1. To change the density of the grid, choose Auto Adjust Density. The default value

is set to 30 pixels, which is generally the best setting for displaying objects.2. Turn off Auto Adjust Density to specify a grid in the current units. The grid density

does not change if you zoom towards or away from the object.3. Select either a Cartesian or Polar coordinate system.4. Enter the values of dX, dY, and dZ for Cartesian coordinates or dR and dTheta for

Polar. Choose Suggested Spacing to fill those fields with the default values.5. Select Grid Visible on (the default) to see the grid.6. Choose OK to accept the values and continue or Cancel to cancel the changes.

Note: To change the grid’s location, hide it, or display it, use the View/Grid Planecommands.



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View/Side WindowThe side window is the region to the side of the screen where the coordinates fields andsnaps are located.

Use the View/Side Window command to move the side window to the left or right of theproject window.

> To move the side window:• Choose View/Side Window/Left to move the side window to the left of the view

window or choose View/Side Window/Right to move the side window to the right.> To change the value of a coordinate in the fields:

1. Select the coordinate you wish to change. This makes the field active.2. Enter the new value of the coordinate in the field. The position of your point in the

view windows automatically changes to correspond with the new value.



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View/ToolbarUse these commands to display or hide the tool bar and change its location.

The tool bar is not available in some modules.

> To move the tool bar to a new location, follow these general steps:1. Choose View/Toolbar.2. Choose one of the six positions to place the tool bar in its new location.

The tool bar moves to its new location. For example, View/Toolbar/Right shows:

Left Moves the tool bar to the left side of the window.Right Moves the tool bar to the right side of the window.Top Moves the tool bar to the top of the window (the default).Bottom Moves the tool bar to the bottom of the window.Show Displays the tool bar (the default). Toggles with View/Toolbar/Hide.Hide Hides the tool bar. Toggles with View/Toolbar/Show.



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View/Command PromptThe command prompt window appears below the project window. This window is whereyou can perform operations in the current module by entering Maxwell commandsthrough the keyboard, instead of accessing them via hotkeys, menus, or the tool baricons. The command prompt is not available in some Maxwell 3D modules.

Use this command to display or hide the command prompt window.

> To display or hide the command prompt:• Choose View/Command Prompt.

> To complete the command name in the command prompt window:• Press Escape.

> To repeat your previous command in the command prompt window:• Press Ctrl-P.

You can also create macros at the command prompt. A macro is a saved series of com-mands which can be repeatedly executed to create identical objects or solve similar prob-lems across different projects.

> To create a macro:1. Choose View/Command Prompt from the modeler menu bar. The command

prompt window appears below the project window.2. At the command prompt, enter FileRecord “Filename.mac” where Filename.mac is

the name of the macro you wish to create. From this point forward, every step willbe recorded into the macro.

3. Enter the script commands you wish to record. The commands that can be enteredare listed in the M3DFS Intro to the Ansoft Macro Language Guide.

4. When you have finished creating the model you want to record, enter FileRecStop.Your macro is now finished and has been recorded.

A check box appears next to this command if the command prompt is visible.



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View/Revert to DefaultsView/Toggle BoundaryVisualization

View/Status BarUse this command to display or hide the status bar at the bottom of the current modulewindow. The status bar displays information about the command that’s currently beingexecuted.

> To display or hide the status bar:• Choose View/Status Bar.

A check box appears next to this command if the status bar is visible.

View/Save Module PreferencesUse this command to save all your settings as the default, such as the visibility of the sta-tus bar, and the location and visibility of the side window, command window, and tool bar.

> To save your default settings:• Choose View/Save Module Preferences.

View/Revert to DefaultsUse this command to erase your current default settings and revert to the original Maxwell3D default settings.

> To erase your settings and revert to the original default settings:• Choose View/Revert to Settings.

Your settings are deleted and replaced with the original default settings.

View/Toggle Boundary VisualizationBoundary/Source Manager

Use this command to toggle the boundary on and off. Toggling the boundary on and offdoes not affect the problem. It merely hides or displays the boundary region.

> To toggle the boundary:• Choose View/Toggle Boundary Visualization.


Maxwell 3D — Coordinates MenuTopics:

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Coordinates MenuCoordinates CommandsUsing Coordinate SystemsCoordinates/Set Current CSCoordinates/Save CurrentCS

Coordinates/DeleteCoordinates/Set Object CSCoordinates/GlobalCoordinates/LocalCoordinates/UnrotatedCoordinates/Rotated

Coordinates MenuUse the commands on the Coordinates menu to:

• Move the origin of the local coordinate system.• Rotate the local coordinate system about the origin along the x-, y-, or z-axis.• Save or delete the current local coordinate system definition.• Switch to a rotated or unrotated local coordinate system.• Switch between local and global coordinate systems.

When you choose Coordinates from the menu bar, the following menu appears:



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Coordinates CommandsThe commands on the Coordinates menu are:

Set Current CS Moves and rotates the coordinate systems:Move Origin Moves the origin of the local coordinate system.Rotate X Rotates the x-axis to a specified point.Rotate Y Rotates the y-axis to a specified point.Rotate Z Rotates the z-axis to a specified point.Use Object CS Sets the current coordinate system to the coordi-

nate system of the selected object.Save Current CS Saves the current local coordinate system settings.Delete CS Deletes one of the saved local coordinate systems.Set Object CS Sets the object’s coordinate system.Global Reverts to the global coordinate system.Local Changes to the local coordinate system.Unrotated Reverts to an unrotated local coordinate system.Rotated Changes to the rotated local coordinate system.

Note: The Coordinates commands determine how the local coordinate system isdefined. They do not affect the visibility or size of the coordinate axes, griddisplay, or other grid settings. To change these things, use the commands onthe View menu.





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Using Coordinate SystemsThe 3D Modeler allows you to define more than one coordinate system, and easily movebetween them, so that you can draw and manipulate objects easily. For example:

• By rotating a coordinate system, you can more easily add objects that are turned at anangle and added relative to each other.

• By moving the origin, you can enter coordinates relative to an existing object, withouthaving to add or subtract the existing object’s coordinates.

• By setting a coordinate system so that it is associated with a specific object, you canuse the coordinate system that is most useful for dealing with that object.

You can toggle back and forth through these coordinate systems, depending on what youare drawing. If you have set or defined all the possibilities, you have the option of any oneof the following coordinate systems:

GlobalThe default coordinate system.

LocalThe current coordinate system, which has been rotated from the global coordinate sys-tem, had the origin defined at a different place in the model, or both. You can save thelocal coordinate system for later use.

Saved localA local coordinate system that has been given a name. These local coordinate systemsare appear in the Coordinates menu. If you select a saved local coordinate system, youcan toggle between it and the global coordinate system using the Global and Local com-mands.

ObjectA local coordinate system that is associated with an object.

Rotated

A local coordinate system that has had the x-, y-, or z-axis rotated from the previous (localor global) coordinate system.

Coordinates MenuCoordinates CommandsUsing Coordinate Systems

GlobalLocalSaved localObjectRotated

Coordinates/Set Current CSCoordinates/Save CurrentCS




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Coordinates/Set Current CSChoose these commands to move or rotate the coordinate systems:

Coordinates/Set Current CS/Move Origin

Use this command to change the location of the origin of the local coordinate system.

> To move the origin:1. Select the point where you wish to define the new origin.2. Choose Coordinates/Move Origin or choose its tool bar icon.

The coordinates of this point appear in the side window, and the origin moves to the newpoint.

Move Origin Moves the origin of the local coordinate system.Rotate X Rotates the x-axis to a specified point.Rotate Y Rotates the y-axis to a specified point.Rotate Z Rotates the z-axis to a specified point.Use Object CS Sets the current coordinate system to the coordinate system of

the selected object.

original origin and new point origin moved to new point

Coordinates MenuCoordinates CommandsUsing Coordinate SystemsCoordinates/Set CurrentCS

Coordinates/Set CurrentCS/Move Origin

Rotating Coordinate Sys-tems

Coordinates/Set CurrentCS/Rotate X

Coordinates/Set CurrentCS/Rotate Y

Coordinates/Set CurrentCS/Rotate Z

Coordinates/Set CurrentCS/Use Object CS

Coordinates/Save CurrentCS




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Rotating Coordinate Systems

Use the Rotate X, Rotate Y, and Rotate Z commands to rotate your local coordinate sys-tem about the x-, y-, or z-axis, toward a specified point. These commands are especiallyuseful when you wish to align the coordinate system with an existing object.

Rotation of an axis through a projection of the current position depends upon the activegrid plane. The axis you wish to rotate must lie on the active grid plane, so that it mayrotate about the perpendicular axis to the new point.

The depth of the rotation depends on the axis line in the active view window:

• If the axis line is a dash-dot line (perpendicular to the grid plane), the axis is rotated togo through the current position.

• If the axis line is solid (on the grid plane itself), the axis is rotated only to go throughthe projection of the current position on the grid plane. In this case, the perpendicularaxis remains fixed, while the other axes move.

original coordinate system withpoint projection

coordinate system with y-axisrotated onto point projection



Rotating CoordinateSystems









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Coordinates/Set Current CS/Rotate X> To rotate the x-axis toward a specified point:

1. Select the point where you wish to define the new x-axis line. The point you mark isthe point that the coordinate system rotates towards.

2. Choose Coordinates/Rotate X.

The x-axis rotates to its new position.

Coordinates/Set Current CS/Rotate Y

Use this command to rotate the y-axis toward a specified point.

> To rotate the y-axis toward a specified point:1. Select the point where you wish to define the new y-axis line. The point you mark is

the point that the coordinate system rotates towards.2. Choose Coordinates/Rotate Y.

The y-axis rotates to its new position.

Coordinates/Set Current CS/Rotate Z

Use this command to rotate the z-axis toward a specified point.

> To rotate the z-axis toward a specified point:1. Select the point where you wish to define the new z-axis line. The point you mark is

the point that the coordinate system rotates towards.2. Choose Coordinates/Rotate Z.

The z-axis rotates to its new position.

Note: When rotating an axis through the projection of the current position, set theactive grid plane to coordinate with the plane along which you wish to rotatethe axis. For example, set the active grid plane to XZ if you wish to rotateeither the x- or z-axis to a new point.












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Coordinates/Set Current CS/Use Object CS

Use this command to move the local coordinate system to match an object’s coordinatesystem. You can modify the local coordinate system with the Coordinates/Set Object CScommand.

> To move the local coordinate system:1. Choose Coordinates/Set Current CS/Use Object’s CS. A list of objects appears

in the side window under the heading Existing Solids.2. Select the name of the object for which you wish to align the local coordinate

system.3. Choose OK to move the local coordinate system to the object’s coordinate system

or choose Cancel to cancel the action.

The local coordinate system now matches the object’s coordinate system.

global coordinate system object coordinate system (of box)












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Coordinates/Save Current CSUse this command to save the definition of the local coordinate system.

> To save the local coordinate system definition:1. Make certain you have defined the coordinate system you want.2. Choose Coordinates/Save Current CS.

The system saves the local coordinate system.

Coordinates/DeleteUse this command to delete one of the saved local coordinate systems.

> To delete a local coordinate system:1. Make certain you have selected the coordinate system you want.2. Choose Coordinates/Delete.

The system deletes the local coordinate system and reverts to the original global coordi-nate system.

Coordinates/Set Object CSUse this command to set the coordinate system of an object.

> To set an object’s coordinate system:1. Choose Coordinates/Set Object CS. A list of objects appears in the side window

under the heading Existing Solids.2. Select the name of the object for which you wish to set the coordinates.3. Choose OK.

The object’s coordinate system is set.





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Coordinates/GlobalUse this command to revert back to the global coordinate system.

> To change to global coordinates:• Choose Coordinates/Global.

A check appears next to this command if global coordinates have been specified.

Coordinates/LocalUse this command to revert back to the most recently used local coordinate system. Thiscommand is disabled if you have not yet defined any local coordinate system with theCoordinates/Move Origin or Coordinates/Rotate commands.

> To change to local coordinates:• Choose Coordinates/Local.

A check appears next to this command if local coordinates have been specified.

Coordinates/UnrotatedUse this command to change to an unrotated local coordinate system. This commandpreserves your local coordinate system origin, but makes all axes parallel to the globalcoordinate system.

> To change to an unrotated local coordinate system:• Choose Coordinates/Unrotated.

A check appears next to this command if unrotated local coordinates have been specified.

Coordinates/RotatedUse this command to restore the original rotation of your local coordinate system.

> To change to a rotated local coordinate system:• Choose Coordinates/Rotated.

A check appears next to this command if rotated local coordinates have been specified.




Maxwell 3D — Lines MenuTopics:

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Lines MenuLines CommandsCurved Lines, Segments,and True Surfaces

Lines/PointLines/Polyline

Creating a PolylineEditing a PolylineArcSplinesTangencyFilleting

Lines/ArcLines/CircleLines/Rectangle

Lines MenuUse the commands on the Lines menu to:

• Draw point objects.• Draw and edit polyline objects.• Create arcs.• Draw circles and rectangles.

When you choose Lines from the menu bar, the following menu appears:

Lines CommandsThe commands on the Lines menu are:

Point Draws a point object in the view windows.Polyline Draws 2D or 3D polyline objects such as a triangles, arcs, and other

irregularly shaped objects.Arc Creates an arc.Circle Draws a circle.Rectangle Draws a rectangle or square.



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Curved Lines, Segments, and True SurfacesWhen you draw a curved polyline object, such as an arc, circle, or spline, or create a fillet,you have the potential of creating a “true surface.” This is a curve modeled with a verylarge number of points. With the Lines/Arc and Lines/Circle commands, you have theoption of specifying the number of segments (facets in solid objects) used in the object.

There is a trade-off between objects approximated with too few and too many segments.If too few segments are specified, the result is a shape that doesn’t look much like theobject. If too many segments are specified, the model becomes more complicated thannecessary, resulting in increased computing requirements. However, the solution accu-racy is generally higher with a true surface. In most cases accept the default values.

Note: The Arc selection in Lines/Polyline creates a true surface. However, theArc selection in Lines/Arc gives you the option of a segmented arc.







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Lines/PointUse this command to draw a point. These points can represent point sources in yourmodel or serve as snap points in more complex geometries.

> To draw a point:1. Choose Lines/Point.2. Double-click on the location in the active window where you wish to draw the point.

The coordinates of the point appear in the coordinates field. Alternatively, you canenter the coordinates of this point in the coordinates fields in the side window.

3. To change the coordinates of the point, select a new point. Alternatively, you canenter the new value of the point in the coordinates fields in the side window. Thepoint moves accordingly with the new coordinate.

4. Choose Enter to enter the Point Position or choose Cancel to cancel the point.5. Select the color of the point.6. Enter the name of the point in the Name field.7. Choose Enter to accept the point.

The point object appears in the view windows.







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Lines/PolylineUse this command to draw irregular 2D or 3D shapes, lines, or objects.Polylines can beused to draw complex and multi-sided two-dimensional or three-dimensional objects. Thisis often more convenient than constraining yourself to circles and rectangles. Triangles,pentagons, and more complex shapes are sketched in this way.

Creating a Polyline

> To draw a polyline:1. Choose Lines/Polyline. A list of polyline or sheet objects appears under the head-

ing Plines/Sheets if any are present in the model. You can select one of these toedit, or enter a name for a new polyline object.

2. Enter a name for the new polyline or accept the default.3. Choose OK to accept the name or choose Cancel to cancel the polyline.4. Optionally, change the name of the line in the Creating field.5. Select a color for the polyline or accept the default.6. Leave the polyline mode set to Add Vert to add a vertex to the polyline.7. If desired, click and hold the Straight button to select Arc or Spline from the type

of segments listed on the pull-down menu.8. Select a beginning point for your polyline, then choose Enter.9. Select the next point in your polyline, using arcs or splines as needed, then choose

Enter.10.Repeat steps 6 through 8 until the polyline is complete. If necessary, choose

Close to place the final point at the start point.

11. If the polyline is closed, select Covered to create a surface using the polyline.12.Choose Done to end the polyline.

Note: • If you are editing a polyline and move or add a point that touches the endof an open polyline, the polylines are automatically stitched together.

• If you are not in the Edit Polyline mode and you move, rotate, or dupli-cate two or more open polylines so that their ends meet, they are notautomatically stitched together. However, if you edit either touchingpolyline, all polylines that touch the edited polyline are stitched togetherwhen you begin editing.







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Editing a Polyline

When editing a polyline (after you have created a polyline) the polyline mode buttonbecomes Ins Vert.

> To edit a polyline:1. If you are not already in Edit Polyline mode, choose Lines/Polyline. A list of

polyline or sheet objects appears under the heading Plines/Sheets if any havebeen created previously.

2. Select the object you want to edit.3. Choose OK to accept the object or choose Cancel to cancel the edit. You are now

in Edit Polyline mode.4. Click and hold the Ins Vert button to access the pull-down menu of polyline editing

modes. Select any of the following:• Choose Ins Vert, Del Vert, or Move Vert to insert, delete, or move any vertex in

the object. Select the vertex, then choose Enter.• Choose Del Edge to delete an edge of the object. Select a point on the edge, then

choose Enter.• Choose Edge Geom to change an existing edge from its current form to a straight

line, an arc, or a spline. To do this:a. Choose Edge Geom from the pull-down menu.b. Select the type of geometry you want the edge of your object to have.c. Click on an existing edge of the object you are editing.d. Choose Enter to accept the new style or Cancel to ignore the change.

• Choose Tangency to make the edge of an arc tangent to the adjacent edge,causing the edges to move smoothly into one another.

5. If desired, choose Join Splines to join any splines together. Choose Split Splinesto separate the splines at the vertices.

6. If desired, choose Close to connect the beginning and end points. Choose Opento create an opening in the polyline.







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Arc

Arcs are curves created by entering the end points on the curve. The center point of thearc is created automatically. You can move the center point of the arc. Since arcs pro-duce true surfaces, use arcs with care, in areas where solution accuracy is critical. To cre-ate an arc using line segments, use the Lines/Arc command.

> To draw an arc:1. Select the first point of the arc, then choose Enter.2. Select the end point in the arc then choose Enter. The modeler draws the default

arc by treating the distance between the two points as the diameter of a circle. Thearc is the half circle described by the two points. The center point of the arc isplaced on the half circle equidistant between the two points.

3. Click and hold the mouse button on the center point to move it. You can modify thearc by moving the center point to the location you desire. This allows you to createa true surface arc by defining three points along it’s surface.

Note: If you select the points by double-clicking the mouse, the center point may be“moved” to the location of your last point.







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Splines

Splines are curves created by entering points on the curve. Since splines produce truesurfaces, use splines with care, in areas where solution accuracy is critical. The followingis an example of drawing a curved line with splines:







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Tangency

Choose Tangency to make the end of an arc tangent to the adjacent line, causing thelines to move smoothly into one another.

> To make two adjacent lines tangent:1. From Edit Polyline mode, click and hold the Ins Vert button to select the

Tangency editing mode.2. Click on the arc you want to change — to make tangent to an adjacent line. If you

use tangency on two straight lines connected at an angle, the line you select will bemoved to extend the attached line.

3. If desired, enter one of the following:• The Radius of the arc. A larger radius will produce a shallower arc. Select Make

Fillet to adjust the position of the endpoints of the arc.• The Included angle, to adjust how many degrees of a circle should be included in

the arc.4. Choose Enter to accept the changes or choose Cancel to ignore them. The edge

that you modified is now tangent to the adjacent edge.







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Filleting

When you make an arc tangent, or change a straight line to an arc, you can select MakeFillet to adjust the endpoints of the arc rather than adjusting the included angle of the arc.

Note: Filleting assumes that the two lines attached to the arc are not parallel, andthat you are filleting an arc between two straight lines.







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Lines/ArcUse this command to draw a 2D arc.

> To draw an arc:1. Choose Lines/Arc. You are prompted to select the arc axis and to enter the center

point of the arc.2. Select the axis — X, Y, or Z — about which the arc is drawn. This axis passes

through the center point, and is orthogonal to the plane in which the arc is drawn.3. Select the center point of the arc in the following way:

a. Do one of the following:• Click on the point in one of the view windows. The coordinates for the point

appear in the X, Y, and Z fields in the side window.• Enter the coordinates for the center point in the X, Y, and Z fields.

b. Choose Enter to select the arc axis and center point.4. Enter the arc’s radius in the Radius field. You can change the radius by clicking on

a point in the active view window or by entering a new value in the Radius field.The circle containing your arc appears, and adjusts as you enter new values.

5. Choose Enter to confirm the radius and starting point.6. Specify the parameters of the arc in the following way:

a. Select Clockwise to specify a clockwise direction for the arc. If you leave thisunselected, the arc has a counterclockwise direction. The direction is from axison which the arc starts.

b. Enter the angle of the arc in the Angle field. This is the angle from the axis onwhich the arc starts. Enter the angle in degrees.

c. Enter the number of line segments to use in approximating the curved surfaceof the arc in the Num Segments field. The number of segments must begreater than 2. Deselect Num Segments to create an arc with a true surface.

d. Enter the name of the arc in the Name field.e. Select the color of the arc.f. Choose Enter to finish specifying the arc. The arc appears in the each of the

view windows.

Note: The axis on which the arc starts follows the right-hand rule. For example, ifthe x-axis is the axis of the arc, the arc would begin on the y-axis (the direc-tion of the x-axis is determined by y cross z).







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Lines/CircleUse this command to draw a 2D circle. Circles can be swept to create cylinders and coils.

> To sketch a circle:1. Choose Lines/Circle.2. Select the Circle Axis.3. Select a point in the active window where you want to place the center of the circle.

Alternatively, enter the coordinates of this point in the coordinates fields.4. Choose Enter to confirm the axis and center of the circle.5. Enter the radius of the circle in the Radius field. You can change this radius by

clicking on a point in the active view window or by entering a new value in theRadius field. The circle will adjust as you enter a new value.

6. Select Num Segments to approximate the shape of a circle using line segments.Otherwise, it is treated as a true surface. Enter the number of segments to usewhen approximating a circle in the field under the Num Segments option. Thenumber of segments must be greater than 2.

7. Select Covered to cover the circle with a face to create a sheet object. It is similarto the Surfaces/Cover Lines command.

8. Enter the name of the circle in the Name field or accept the default name.9. Choose the Color box to change the color of the circle.10.Choose Enter to accept the circle or choose Cancel to cancel the circle.

The circle appears in each of the view windows. Like arcs and splines, circles are notdependent on segments, as in previous versions of the Maxwell 3D. They are treated astrue surfaces with respect to meshing and sweeping.







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Lines/RectangleUse this command to create a square or rectangle. You can sweep a square or rectangleto form a box.

> To draw a rectangle or square:1. Choose Lines/Rectangle.2. Select the point where you want a corner of the square to appear.3. Choose Enter to enter the First point of the rectangle. A row of Rectangle Plane

buttons appears in the side window.4. Select the rectangle plane in which you wish to place the base of the rectangle.5. Enter the size of the square in the Size fields. Alternatively, you can click on the

point where you wish to place the opposite vertex of the rectangle.6. Optionally, deselect Covered to make the created polyline an open object.

Covered object are considered to be 2D solids.7. Enter the name of the rectangle or accept the default.8. Click on the Color box to change the color of the rectangle. A palette of colors

appears.9. Select a new color.10.Choose Enter to accept the rectangle or choose Cancel to cancel the rectangle.

Below is an example of two rectangles shown in the 3D view window.






Maxwell 3D — Surfaces MenuTopics:

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Surfaces MenuSurfaces CommandsSurfaces/Cover LinesSurfaces/Uncover FacesSurfaces/Detach FacesSurfaces/SectionSurfaces/ConnectSurfaces/Stitch

Surfaces MenuUse the commands on the Surfaces menu to:

• Change a polyline object into a sheet object.• Cover or uncover the faces of objects to form sheet objects or polylines.• Detach the faces of objects.• Create cross-sections of 3D objects.• Connect multiple polyline objects into a 3D sheet object.• Stitch two or more sheet objects together to act as a single object.

When you choose Surfaces from the menu bar, the following menu appears:



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Surfaces CommandsThe commands on the Surfaces menu do the following:

Surfaces/Cover LinesUse the Surfaces/Cover Lines command to cover closed polyline objects with faces tocreate sheet objects. Essentially, a sheet object is an object which has a surface, but novolume. When you sweep a polyline object, the ends of the object are open, thus yourobject is not truly a solid. When you use this command prior to a sweep, you convert yourpolyline to a sheet. Sweeping this sheet will allow you to create a solid.

> To convert a polyline to a sheet object:1. Choose Surfaces/Cover Lines. A list of closed polylines appears under the

heading Closed Plines in the side window.2. Select the names of the polyline to highlight them.3. Choose OK to select the polylines or Cancel to cancel the action.

The polylines are now sheet objects which may be swept to form a solid, used as termi-nals in setting up boundaries in the Boundary/Source Manager, or can be used in stitch-ing operations.

Cover Lines Changes a closed polyline object into a sheet object.Uncover Faces Changes the face of a 2D object to a polyline, or changes the faces

of a 3D solid to a 3D sheet object.Detach Faces Detaches the faces of objects from the objects themselves.Section Creates a planar cross-section of 3D objects, but leaves the original

objects intact.Connect Connects two or more polyline objects by creating surfaces between

them.Stitch Joins sheet objects with touching edges together as a single object.




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Surfaces/Uncover FacesUse this command to uncover the object faces of sheet objects which leaves a closedpolyline object. You may also uncover the faces of solid objects leaving them as sheetobjects.

> To uncover the faces of an object:1. Choose Surfaces/Uncover Faces.2. Select the faces of the objects in the view window that you wish to uncover.3. Choose Enter to accept the faces or Cancel to cancel the action.

The object faces are now uncovered, leaving open faces on the objects.

Surfaces/Detach FacesUse this command to detach the object faces of sheet objects to leave a closed polylineobject. You may also detach the faces of solid objects leaving them as sheet objects.

> To uncover the faces of an object:1. Choose Surfaces/Detach Faces.2. Select the faces of the objects in the view window that you wish to uncover.3. Choose Enter to accept the faces or Cancel to cancel the action.

The object faces are now uncovered, leaving open faces on the objects.




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Surfaces/SectionUse this command to create cross-sections of 3D objects on the xy, yz, or xz plane. Thecross-sections are created as planar, closed polyline objects.

• If you want the section plane to be elsewhere than the global coordinate system, setyour local coordinate system first using the Coordinates/Move Origin orCoordinates/Rotate commands.

• Sectioning only works on solid objects, although you may see sheet objects listedwhen you select objects for sectioning. If you select these, they will simply be ignored.

> To create a cross-section of an object:1. Make sure the axes you want to use for the cross-sectioning plane are positioned

correctly.2. Choose Surfaces/Section. The cursor changes to a pointing icon.3. Select the section plane you will use to divide the object.4. Choose Enter to accept the section plane (or choose Cancel to cancel the action).

A list of solid objects in the model appears in the side window.5. Select the solids you want to section, using the mouse cursor or the list in the side

window.6. Choose OK to accept the objects or choose Cancel to cancel the action.

A closed polyline object is created for each part of each object that is sliced by theselected axis. The sectioned objects are unchanged.




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Surfaces/ConnectUse this command to connect two or more polyline objects by creating surfaces betweenthem. You may form complex 3D sheet objects with this command and later convert thesesheet objects into solids using the Surfaces/Stitch or Surfaces/Cover Sheets com-mands.

> To connect two or more polylines together:1. Choose Surfaces/Connect. A list of polylines appears in the side window under

Existing Wires.2. Select the names of the objects in the order that you want to connect them.

Alternatively, select the objects themselves in the view windows in the order youwish to connect them.

3. Choose OK to accept the connection or choose Cancel to cancel the action.

The polylines are now connected with a surface, creating a sheet object. The name of theconnected objects appears as Connect. The polyline objects remain intact after the Con-nect object has been formed.




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Surfaces/StitchUse this command to stitch sheet objects together. There is no limit to the number ofsheet objects that can be stitched together as long as the surfaces of the objects are incontact with one another.

> To join two or more objects:1. Choose Surfaces/Stitch. A list of all sheet objects in the model appears.2. Select the objects you wish to stitch together.3. Choose OK to accept the stitch or choose Cancel to cancel the action.

The objects are now stitched together as one. You will not be able to treat any of theobjects individually after they are stitched. The stitched object retains the name of the firstobject to be stitched.

If the stitched sheet objects form a completely closed object, the object formed becomesa solid. If the objects you attempt to stitch together are not in contact with one another,those objects will be excluded from the stitching and may result in creating an emptyobject.

Note: In Maxwell 3D, the objects being stitched together are not preserved. There-fore, if you wish to keep a copy of the objects, do the following:

1. Make a copy of the objects, using Edit/Copy.2. Perform the stitch operation.3. Paste the objects back into the project, using Edit/Paste.



Maxwell 3D — Solids MenuTopics:

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Solids MenuSolids CommandsSolids/BoxSolids/CylinderSolids/HelixSolids/Sweep

Solids/Sweep/Around AxisSolids/Sweep/Along Vec-tor

Solids/Sweep/Along PathSolids/Sweep/Along PathWith Twist

Solids/UniteSolids/IntersectSolids/SubtractSolids/SplitSolids/Cover Surfaces

Solids MenuUse the commands on the Solids menu to:

• Draw simple 3D objects such as cylinders, boxes, cones and spheres.• Draw a spiral or helix.• Sweep a 2D object to create a 3D object. 2D objects can be swept:

• Along a vector that you enter.• Around the x-, y-, or z-axis.• Along an open or closed 2D polyline or 3D object (optionally, with a twist).

• Unite, intersect, split, or subtract 3D objects to create more complex objects.• Cover open surfaces to create solids objects.

When you choose Solids from the menu bar, the following menu appears:



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Solids CommandsThe commands in the Solids menu do the following:

Box Draws a rectangular or square box.Cylinder Draws a cylinder.Helix Draws a 2D or 3D helix by sweeping an existing 2D polyline object.Sweep Draws a 3D object by sweeping a 2D object:

Around Axis Around the x-, y-, or z-axis.Along Vector Along a vector that you specify.Along Path Along an open 2D polyline object.Along Path With Twist Along an open 2D polyline object with a twist.

Unite Unites two 3D objects into a single object for boolean operations.Intersect Takes the intersection of two 3D objects, creating a new object.Subtract Subtracts one 3D object from another, creating a new object.Split Splits an object on the XY, YZ, or XZ planes to produce two new objects.CoverSurfaces

Covers open objects, converting them into solids.







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Solids/BoxUse this command to draw a rectangular 3D object.

> To draw a rectangular or square box:1. Choose Solids/Box.2. Select the point in the active window where you wish to place the box base vertex.

The coordinates of this point appear in the side window. You can change thesecoordinates by double-clicking on the field of the coordinate you wish to modifyand entering a new value. The object in the view window changes accordingly.Alternatively, you can use the keyboard to enter the coordinates of this point in thecoordinates fields.

3. Choose Enter to accept the Box Base Vertex.4. Enter the X, Y, and Z dimensions of the box in the Enter Box Size field in the side

window. As you enter each value, the view window will display the change indimensions. You can click on a point in the view windows to represent the oppositevertex, but entering the values will give you a more precise and controlled box.

5. Enter a name for the box.6. Click on the Color square to select a new color. A palette of colors appears.7. Select a new color.8. Choose Enter to accept the box or choose Cancel to cancel the box.







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Solids/CylinderUse this command to create a cylinder. Cylinders can simulate coils when you subtract asmaller cylinder from a large one.

> To draw a cylinder:1. Choose Solids/Cylinder.2. Select the point in the view window where you wish to place the center of the base

of the cylinder. The coordinates of this point will be displayed in the side window.You can change these coordinates by double-clicking on the field of the coordinateyou wish to modify and entering a new value. The object in the view windowchanges accordingly. Alternatively, you can use the keyboard to enter thecoordinates of this point in the coordinates fields.

3. Choose Enter to accept the Base center.4. Choose the Cylinder Axis to define the perpendicular axis of the cylinder. The

axis will be automatically defined as the axis that is perpendicular to the plane inwhich the base rests. For example, if the base was drawn in the xy plane, thecylinder axis is the z-axis.

5. Enter the radius and height of the cylinder in the Radius & Height fields in the sidewindow.

6. Enter a name for the cylinder.7. Click on the Color square to select a new color. A palette of colors appears.8. Select a new color.9. Choose Enter to accept the cylinder or choose Cancel to cancel the cylinder.

Note: If you create a cylinder with height of zero, the software creates a circularsheet object.







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Solids/HelixUse this command to sketch a helix or spiral in the view window. The object that yousweep into a helix must have only straight edges.

> To draw a helix:1. Choose Solids/Helix. A list of polyline and sheet objects in the model appears in

the side window.

2. Select the name of one of these objects to highlight it. The name of the objectappears in the Helix Profile box.

3. Choose OK at the bottom of the list to select the item or choose Cancel to cancelthe action.

4. In the Helix Parameters window, select the Helix Axis.5. Specify the Turn direction.6. Enter the pitch of the helix in the Helix Pitch field. This is the distance between

successive turns of the helix. The units for pitch are those you specified for themodel.

7. Enter the Number of turns in the helix. This specifies the number of completerevolutions the object makes about the helix axis.

8. Enter the Number of segments per turn. The system approximates the curvedsurfaces of the helix using segments. This specifies the number of segments touse approximating each turn of the helix. Generally use no fewer than 12 or nomore than 36 segments per turn.

9. Enter the Radius change per turn or accept the default. This specifies theamount to increase or decrease the radius of the helix each turn. The units for theradius are those you specified for the model.

10.Enter the name of the helix in the Name field.11.Select a color from the palette.12.Choose OK to enter the helix parameters or choose Cancel to cancel the action.

Warning: Keep the following in mind when creating a helix:• The object you select to sweep for the helix must be a segmented

object. You cannot use an object with a true surface, such as an arcor spline.

• The objects you sweep to form the helix are deleted.







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Solids/SweepUse these commands to create a 3D object by sweeping a 2D object.

2D objects that can be swept into a 3D object include:

• 2D objects created using Lines/Circle, Lines/Rectangle, or Lines/Polyline.• 2D objects created in the 2D Modeler.• 2D objects created in PlotData by saving a plot as a *.sm2 file.

If you sweep an open object, the resulting object will have open ends. If you sweep asheet object, the resulting object is a solid. The 2D object need not be orthogonal to thesweep path.

Around Axis Around the x-, y-, or z-axis.Along Vector Along a vector that you specify.Along Path Along an open or closed 2D polyline object.Along Path With Twist Along an open or closed 2D polyline object with a twist.

Note: In Maxwell 3D, the 2D objects being swept are not preserved. Therefore, ifyou wish to keep a copy of the 2D objects, do the following:

1. Make a copy of the objects, using Edit/Copy.2. Perform the sweep.3. Paste the 2D objects back into the project, using Edit/Paste.







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Solids/Sweep/Around Axis

Use this command to sweep an object around a defined axis. Sweeping circles around anaxis is a convenient way to create an open coil loop.

Before using this command, keep the following guidelines in mind:

• The object must lie in the plane of the axis you are sweeping around. For example, ifyou are sweeping an object around the z-axis, the object must lie in the xz or yz plane.

• The normal of the object’s plane faces must be perpendicular to the axis about whichyou are sweeping.

• The object may not cross the axis about which it is being swept.

> To sweep the object around an axis:1. Choose Solids/Sweep/Around Axis. A list of profiles appears in the Profiles field.2. Select the object you wish to sweep. You may select more than one.3. Choose OK to select the objects. Sweep controls appear in the side window.4. Select the axis that you wish to sweep the object around.5. Enter the angle through which to sweep the object in the Angle of sweep field.

The value must be between -360 and 360 degrees.6. Enter the number of legs the object is swept through in the Number of Steps field.

For example, enter 4 for a square shape (for 360 degrees). Leave the default valueof zero for a smooth, circular sweep, which creates a true surface.

7. Enter the draft angle in the Draft Angle field. This indicates the angle at which theprofile expands or contracts as it is swept. The Extended and Round optionsbecome available.

8. If necessary, choose whether the sweep values will be Extended or Round.Extended values will leave the swept object with the sharp edges of the originalobject, while Round values will leave the swept object with rounded edges.

9. Choose Enter to accept your values or choose Cancel to cancel the action.

A new sheet or solid object is drawn in the view windows. The new object has the nameand color of the original profile.

Note: The Draft Angle is only available if the sweep angle is greater than -360degrees and less than 360 degrees.


Solids/Sweep/AroundAxis

Solids/Sweep/Along Vec-tor





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Solids/Sweep/Along Vector

Use this command to sweep a polyline or closed profile along a vector. Sweeping an openor closed polyline will result in an open object. You must use the Surfaces/Cover Outlineor the Surfaces/Cover Sheets command to create solids from sheet objects andpolylines.

> To sweep the object along a vector:1. Choose Solids/Sweep/Along Vector. A list of profiles appears in the side window.2. Select the names of the objects you wish to sweep along an axis.3. Choose OK to select the objects. The Enter Vector fields appears.4. Enter the x, y, and z components of the vector that you wish to sweep the objects

along. The length of this vector appears in the Vector Length field. If necessary,double-click on this field and enter a new vector length. The coordinates changeaccordingly.

5. Choose Enter.6. Enter a name for the swept object.7. Choose Enter to accept the object or choose Cancel to cancel the sweep.

A new sheet or solid object is drawn in the view windows. The new object has the nameand color of the original profile. The following figure shows a polyline swept to create a 3Dsheet object:


Solids/Sweep/Around AxisSolids/Sweep/AlongVector





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Solids/Sweep/Along Path

Use this command to sweep a polyline or sheet along a path defined by a polyline.Sweeping an uncovered polyline results in an open object; sweeping a sheet objectresults in a solid. Use the Surfaces/Cover Lines or the Solids/Cover Surfaces com-mand to create solids from sheet objects and polylines.

When you are sweeping an object along a path, keep in mind that one of the endpoints ofthe path must lie in the same plane as the object being swept.

> To sweep the object along a path:1. Create the polyline you want to use as a path. The red path in the following figure

will be used to sweep the circle at its right end:

2. Choose Solids/Sweep/Along Path. A list of all visible polylines and sheet objectsappears in the side window.

3. Select the names of the objects you wish to sweep along a path.4. Choose OK to select the objects. A list of the polylines appears in the side window.

These polylines will form the path along which you will sweep the object.5. Choose the polyline to sweep the profile along. The name appears in the Sweep

Path field.6. Choose OK to select the polyline. A hand-shaped icon appears, pointing to the

blank fields in the side window.



Solids/Sweep/AlongPath

Solids/Sweep/Along PathWith Twist




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7. If necessary, double-click on the Draft Angle field and enter a new value.8. If necessary, choose whether the sweep values will be Extended or Round.

Extended values leave the swept object with the sharp edges of the originalobject, while Round values leave the swept object with smooth, rounded edges.

9. Choose Enter to accept the object or choose Cancel to cancel the sweep. Thenew object has the name and color of the original profile. The following figureshows the result of sweeping the circle in the previous figure along a polyline:



Solids/Sweep/AlongPath

Solids/Sweep/Along PathWith Twist




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Solids/Sweep/Along Path With Twist

Use this command to sweep a polyline or closed profile along a path, twisting the profilesas they are swept. This is useful when generating irregularly shaped 3D objects. Sweep-ing an uncovered polyline results in an open object; sweeping a sheet object results in asolid. Use the Surfaces/Cover Lines or the Solids/Cover Surfaces command to createsolids from sheet objects and polylines.

When you are sweeping an object along a path with a twist, keep the following things inmind:

• If you are twisting the object you are sweeping (there is an Angle of Twist value otherthan zero), the path must be smooth and continuous, without any sharp bends.

• One of the endpoints of the path must lie in the same plane as the object being swept.

> To sweep the object:1. Create the polyline you want to use as a path. The red path in the following figure

will be used to sweep the circle at its right end:

2. Choose Solids/Sweep/Along Path With Twist. A list of visible polylines andsheet objects appears.

3. Select the object to sweep along a path.4. Choose OK to select the object. A list of polylines appears. One of these polylines

will form the path along which you sweep the object.



Solids/Sweep/Along PathSolids/Sweep/AlongPath With Twist




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5. Select the polyline to use as a path. The name of the object appears in the SweepPath field.

6. Choose OK to accept the selection. A hand-shaped icon appears, pointing to theblank fields in the side window.

7. Enter the angle of the twist in the path in the Angle of Twist field. This is thenumber of degrees the profile will rotate as it is swept through the complete path.The following figure shows a circle (with 8 segments) twisted through 180 degrees.

8. Choose Enter to accept the sweep parameters or Cancel to cancel the sweep.The new object has the name and color of the original profile.



Solids/Sweep/Along PathSolids/Sweep/AlongPath With Twist




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Solids/UniteUse this command to join two or more overlapping objects into one solid object. This com-mand unites the objects at the point of intersection.

> To unite two objects:1. Choose Solids/Unite. A list of visible Existing solids appears in the side window.2. Select the names of the solids that you wish to unite. The united solid retains the

name and color of the first solid.3. Choose OK to accept the objects or Cancel to cancel the action.

The objects are now united into one. If the objects do not overlap, an error occurs. Forexample, you will not be able to unite a sphere with a cylinder if they do not touch.

Solids/IntersectUse this command to form a new object by taking the intersection of two or more objects.

> To intersect the objects:1. Choose Solids/Intersect. A list of visible solid objects appears in the side window.2. Select the solids that you wish to take the intersection of.3. Choose OK to accept the object or choose Cancel to cancel the action.

The objects vanish, leaving only the new object that was formed from the intersection.

Note: The objects being joined are not preserved for later use.Therefore, if you wish to keep a copy of the 2D objects, do the following:


Note: The objects being intersected are not preserved for later use.

Warning: If the objects you choose to intersect do not overlap, the result is a null objectand both objects vanish.







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Solids/SubtractUse this command to subtract one group of objects from another.

> To subtract one item from another:1. Choose Solids/Subtract. A list of visible Existing solids appears in the side

window.2. Select the solids from which you wish to subtract.3. Choose OK to select the objects.4. Select the names of the solids that you wish to subtract from the first.5. Choose OK to select the objects.

The second group of objects is subtracted from the first one, resulting in new objects. Thenew objects retain the name of the first group of objects.

Note: The objects being subtracted are not preserved for later use.Therefore, if you wish to keep a copy of the 2D objects, do the following:


Intersecting box and cylinder. Box subtracted from cylinder(cylinder selected first).







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Solids/SplitSplits objects on the xy, yz, or xz plane.

• If you want the section plane to be elsewhere than the global coordinate system, setyour local coordinate system first using the Coordinates/Move Origin orCoordinates/Rotates commands.

> To divide an object into smaller pieces:1. Choose Solids/Split. The cursor changes to a pointing icon.2. Select the Split plane that you will use to split the object.3. Select which fragments you want to keep — Above the split plane, Below it, or all

pieces on Both sides of the plane. Any fragments not identified for keeping arediscarded.

4. Choose Enter to accept the split or Cancel to cancel the action.5. Select the names of the existing solids that you want to split.6. Choose OK to accept the solids or Cancel to cancel the action.

The objects are divided along the split plane.

Solids/Cover SurfacesUse this command to cover all open areas in the sheet objects of your model. For exam-ple, if you have a hollow cylinder which has open ends, this command will cover thoseends to form a solid cylinder. The open edges must form closed polylines when taken bythemselves.

> To cover sheet objects to form a solid:1. Choose Solids/Cover Surfaces. A list of sheet objects appears in the side

window.2. Select the sheets you wish to cover.3. Choose OK to accept the cover or Cancel to cancel the action.

The sheet objects are now solid objects.

Note: • Unlike the seemingly similar Surfaces/Section command, the splitobjects are not left unchanged.

• Also unlike the Surfaces/Section command, sheet objects can be splitinto more than one object.






Maxwell 3D — Arrange MenuTopics:

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Arrange MenuArrange CommandsArrange/Move

Using the MouseUsing the Keyboard

Arrange/RotateArrange/MirrorArrange/Scale

Arrange MenuUse the commands on the Arrange menu to:

• Move objects to new locations in the window.• Rotate objects around an axis.• Mirror objects across a plane.• Change the scaling sizes of objects.

When you choose Arrange from the menu bar, the following menu appears:

Arrange CommandsThe commands on the Arrange menu are:

These commands remain inactive until an object has been selected.

Move Moves the selected objects to the location you specify.Rotate Rotates the selected objects around the x-, y-, or z-axis.Mirror Mirrors the selected objects about any plane.Scale Changes the scale of the selected objects, resizing them.



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Arrange/MoveUse this command to move selected objects by:

• Picking and moving them with the mouse.• Entering the cartesian coordinates where they are to be moved.• Entering their new location as an offset from their current location.

The exact method that you use depends on the way your geometric model is set up andyour personal preference.

Using the Mouse> To move objects using the mouse:

1. Select the items by clicking on them or with the Edit/Select command.2. Choose Arrange/Move.3. Select the point you wish to be the anchor point.4. Choose Reset Start from the side window.5. Select the target point.6. Choose Enter to accept the new location or choose Cancel to cancel the change.

All selected items move the distance determined by the offset between the base point andthe target point.

Using the Keyboard> To move the selected items using the keyboard:

1. Select the items by clicking on them or with the Edit/Select command.2. Choose Arrange/Move.3. Enter the displacement vector components in the Enter Vector field.4. The length of the vector is displayed in the Vector length field. You can change

this number directly or reenter coordinates if the number is unsatisfactory.5. Choose Enter to accept the new location or choose Cancel to cancel the change.

All selected items move the distance and direction determined by the offset between thebase point and the target point.






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Arrange/RotateUse this command to rotate the selected objects about an arbitrary axis.

> To rotate items about an axis:1. Select the items by clicking on them or with the Edit/Select command.2. Choose Arrange/Rotate. New fields appear in the side window.3. Select the axis about which you wish to rotate the selected objects.4. Enter the Angle of the rotation in the Angle field or accept the default. This is the

angle at which the objects will rotate about the axis.5. Choose Enter to accept the rotation or choose Cancel to cancel the rotation.

The selected object (or group of objects) rotates about the selected axis by the specifiedangle. To rotate and copy objects, use the Edit/Duplicate/Around Axis command. Toselect clockwise or counter-clockwise rotation, change the sign of the angle.






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Arrange/MirrorUse this command to mirror selected objects about a plane. The plane is selected bydefining a point on the plane and a normal point. This command allows you to move anobject to a more suitable location.

> To mirror objects across a plane:1. Select the items by clicking on them or with the Edit/Select command.2. Choose Arrange/Mirror.3. Select a point on the plane where you wish to mirror the object. The coordinates of

the point you selected appear in the coordinates fields. The angle and radianmeasure of the mirror also appear. Alternatively, you can use the keyboard toenter the coordinates of the point in the side window.

4. Choose Enter to accept the point on the plane. You are prompted to select anormal point.

5. Select the normal point. Again, the coordinates and the angle of the new pointappear in the coordinates fields. Alternatively, you can use the keyboard to enterthe point in the coordinates fields in the side window.

6. Choose Enter to accept the coordinates or Cancel to cancel the mirror.

The selected items are mirrored about the plane you selected.

To mirror and copy objects across a plane, use the Edit/Duplicate/Mirror command.






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Arrange/ScaleUse this command to change the scale of an object’s dimensions.

The scale of an object is its size in relation to its vertices and an anchor point. For exam-ple, if you specify 2 as a scale factor for a geometric object, its vertices are moved so thatthe distance between them and the anchor point is doubled, making the object twice aslarge. Similarly, if you specify 0.5 as the scale factor, the vertices move so that the dis-tance between them and the anchor point is halved, making the object half as large. Theobject is positioned differently depending on the location of the coordinate system’s origin.

> To rescale the dimensions of an object:1. Select the items with the Edit/Select command.2. Choose Arrange/Scale. The Scaling Factor field appears in the side window.3. Enter the scale factor.4. Choose Enter or press Return to accept the scaling. Choose Cancel to cancel the

scaling.

The selected items are rescaled about the current coordinate system’s origin.





Maxwell 3D — Options MenuTopics:

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Options/Region/DefineOptions/Region/Fit AllOptions/Region/HideOptions/Region/ShowOptions/Region/VerifyBackground ObjectOptimal Size of the Model-ing Region

Options/ExpressionsCommon FunctionsDefining a FunctionChanging a FunctionDeleting FunctionsDataset


3D Post Processor Prefer-ences

Options MenuUse the commands on the Options menu to:

• Select the units of measurement for the geometric model.• Check to see if your objects overlap.• Specify the size of the solution region.• Change the color of the selected objects.• Display the expression evaluator panel, which may be used to enter, modify, and

calculate algebraic expressions.• Set the color in which selected objects are highlighted.• Specify the preferences for new projects.

When you choose Options from the menu bar, a menu similar to the following oneappears:



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Options CommandsThe commands on the Options menu are:

Units Selects the units of measurement for drawing the geometricmodel.

Check Overlap Checks to see if any objects in the modeling regions occupythe same space.

Region Sets the size of the solution region. You must set the size ofthe problem region before saving the final geometric model.Otherwise, the default — a region approximately equal tothat of the smallest bounding box which contains all objects— is used.

Expressions Lists the mathematical expressions in the problem.Default Color Changes the color of selected objects and sets the default

color of new objects.Selection Color Sets the color of a selected object to a new selection color.Preferences Sets default settings for the units, grid size and type, shad-

ing, and color preferences for new projects. Also sets thedefault file type as ascii or binary.In the 3D Post Processor, this defines the default lighting set-tings, and number of displayed color keys.








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Options/UnitsUse this command to specify the units of measurement for drawing the geometric model.

When the units of measurement have been specified, the modeler will assign those unitsto the objects in the view windows. You can then choose to display the new units on theproject grid or rescale the entire grid to the new units. This will not affect the units in thesolution, which will always be given as SI units.

> To specify the units of measurement:1. Choose Options/Units. The Drawing Units window appears.2. Choose Select Units to select the new units for your model.3. Specify how the change in units will affect the model:

• Choose Display in New Units (the default) to display the dimensions in the newunits without changing their scale. For instance, choosing centimeters as the newunit causes a dimension of ten millimeters to be displayed as one centimeter.

• Choose Rescale to New Units to change the scale so that all dimensions areconverted to the new units. For instance, choosing centimeters as the new unitcauses a dimension of ten millimeters to become ten centimeters.

4. Choose OK to accept the new units or choose Cancel to cancel the change.

Options/Check OverlapUse this command to see if any objects in the modeling regions occupy the same space.This is important because the final geometry will be invalid if any of the objects overlap.

> To check a modeling region of object overlaps:• Choose Options/Check Overlap.

A response window appears to tell you if it has found any overlaps. Overlapping objectscan be joined with the Solids/Unite command, intersected with the Solids/Intersectcommand, subtracted with the Solids/Subtract command, or moved to a new positionwith the Arrange/Move command.








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Options/RegionUse these commands to define the size of the region in which the mesh is created. Thesize of the region is defined automatically the first time you save, and usually does notneed to be modified.

Visualize the modeling region as a tight, rectangular box that is approximately equal to thesmallest box which completely encloses the structure.

The system generates a field solution for the entire modeling region — which can be quitelarge if you leave it set to its default size. In most cases, it makes sense to reduce the sizeof the problem region in order to conserve computing resources and speed up the solu-tion time. In addition, when defining boundaries it is often necessary to define the size ofthe solution region so that one or more boundaries are flush against the structure.

The area outside the problem region is known as the background. No solution or meshgeneration occurs in this region.

The commands in the Options/Region submenu are:

Define Defines the size and coordinates of the modeling region.Fit All Fits the entire modeling region into the window and scales the size pro-

portionally.Hide Hides the boundary of the modeling region.Show Shows the boundary of the modeling region.Verify Verifies the correctness of the modeling region.








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Options/Region/Define

Use this command to define the coordinates and size of the modeling region.

> To define the size of the problem region in the active window:1. Choose Options/Region/Define.2. In the coordinates fields, enter the x-, y-, and z-coordinates of the first vertex you

wish to define. Optionally, you can enter new values for the radian and angularvalues of the mesh region. Accept the default to define the first vertex as the origin.You can also define this point by clicking on the point you wish to define. Thecoordinates of the point appear in the coordinates fields in the side window.

3. Choose Enter to accept the values or Cancel to cancel the action.4. Enter the X, Y, and Z dimensions in the fields under Enter region size.5. Choose Enter to accept the values or choose Cancel to cancel the action.

If the box you defined is too small to accommodate all the objects in the model, the regionis automatically expanded.

Options/Region/Fit All

Use this command to fit the entire modeling region in the active view window.

> To fit the entire problem region into the active view window:1. Choose Options/Region/Fit All.2. If necessary, enter the Padding Percent. This provides a space between the

boundary of the modeling region and the border of the view window.3. If necessary, choose the Round off button to round the percentage scaling.4. Choose OK to accept the values.

The entire region appears in the active window.








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Options/Region/Hide

Use this command to hide the boundary of the modeling region.

> To hide the boundary in the active window:• Choose Options/Region/Hide. This command toggles with the Options/Region/

Show command.

The boundary of the modeling region vanishes.

Options/Region/Show

Use this command to display the boundary of the modeling region.

> To show the boundary of the modeling region in the active window:• Choose Options/Region/Show. This command toggles with the Options/Region/

Hide command.

The boundary of the modeling region appears.

Options/Region/Verify

Use this command to verify that the model in enclosed within boundary region. This com-mand checks to see if any objects extend beyond the region.

> To verify the region:• Choose Options/Region/Verify. The response screen will appear to tell you if any

objects in the model extend beyond the problem region. If any objects exist outsidethe region, they are highlighted, alerting you to the error.








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Background Object

The part of the mesh region not occupied by objects is considered to be the “background”object. The background extends to the boundaries of the mesh region and fills in anyvoids not occupied by objects. Since the background object is defined as a perfect con-ductor, no solution is generated inside the background (even though an initial mesh isgenerated for it).

Outer Boundaries

The region outside the problem space is not considered to be part of the problem. Theeffect of electromagnetic sources beyond the background can only be modeled by placingthe appropriate boundary conditions on the outer walls of the problem space. If no bound-ary conditions are specified here, the area beyond the problem region is ignored by thesystem. No solution is generated there.

Excluded (Non-Existent) Background

When assigning materials, you can declare that an object is excluded — in other words,that it is not part of the problem region and effectively does not exist. Excluding the back-ground object allows you to limit the field solution to objects which you have defined. Sur-faces exposed to the background become the outer boundaries of the problem region.This is useful when you are assigning boundary conditions to edges of irregularly shapedobjects. For instance, you cannot assign matching boundaries to the edges of a pie-shaped model unless the background is excluded from the solution region.

If you only want to compute a solution inside the objects you created, the size of the mod-eling region does not matter. Accept the default size and subsequently exclude the back-ground object.








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Optimal Size of the Modeling Region

The optimal size of the modeling region varies from problem to problem. The distributionof energy and the necessary boundary conditions and sources play an important role.

For example, in cases where the energy associated with a field is concentrated in a smallregion of a structure — perhaps an air gap — a large problem region is not necessary.Size the problem region so that its boundaries are where the field strength is near zerowith respect to the model.

There may be times where you want to model half of a structure in order to take advan-tage of symmetry. To properly model the structure, the problem region must be sized sothat the plane of symmetry lies on the edge of the problem region.

Finally, in cases where you plan to attach outer terminals to objects, it makes sense todefine the problem region so that all outer terminals coincide with a boundary of the prob-lem region. Because outer terminals must be exposed to a region in which no solution isgenerated, the only alternative would be to expose the terminals to the background andthen declare the background to be non-existent. In many cases, it is easier to define theproblem region to be the appropriate size in the first place.


Options/Region/DefineOptions/Region/Fit AllOptions/Region/HideOptions/Region/ShowOptions/Region/VerifyBackground ObjectOptimal Size of the Mod-eling Region






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Options/ExpressionsChoose Options/Expressions to add, modify, or display the functions used in definingyour model. These functions represent various quantities, such as angles and distances,in your model. The following window appears:

Common Functions

The following legal functions may be used to define mathematical expressions:

/ Division.+ Addition.- Subtraction and unary minus.* Multiplication.% Modulus.** Exponentiation.<< Left shift.>> Right shift.= Assigns.== Equals.!= Not equals.> Greater than.








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< Less than.>= Greater than or equal to.<= Less than or equal to.& Bitwise AND.| Bitwise OR.^ Bitwise XOR.~ 1’s compliment.&& Logical AND.II Logical OR.! Factorial.if IF statement.pwlx Piecewise linear function in the x-direction.pwly Piecewise linear function in the y-direction.dset Defines a dataset. Syntax: dset((x0, y0), (x1, y1), ... (xn, yn))sign Returns the sign of an argument. Syntax: sign (x)abs Absolute value. Syntax: abs (x)exp Exponential. Syntax: exp (x) = ex

pow Raises the specified value to the specified power. Syntax: pow (x, y) = xy

ln Natural log. Syntax: ln (x)log Log base 10. Syntax: log (x)lg Log base 2. Syntax: lg (x)sqrt Square root. Syntax: sqrt (x)floor Rounds down. Syntax: floor (x)ceil Rounds up. Syntax: ceil (x)round Rounds to nearest. Syntax: round (x)rand Generates a random number between 0 and 1. Syntax: rand ()deg Convert radians to degrees. Syntax: deg (x)rad Convert degrees to radians. Syntax: rad (x)sin Sine. Syntax: sin (x)cos Cosine. Syntax: cos (x)tan Tangent. Syntax: tan (x)








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All trigonometric expressions expect their arguments to be in degrees, and the inversetrigonometric functions’ return values are in degrees. These function names are reservedand may not be used as variable names.

Consult the documentation on the Expression Evaluator for more information on the intrin-sic functions and variables used to define expressions.

asin Arc sine. Syntax: asin (x)acos Arc cosine. Syntax: acos (x)atan Arc tangent. Syntax: atan (x)atan2 Arc tangent (in the range of -n/2 to n/2). Syntax: atan2 (x)sinh Hyperbolic sine. Syntax: sinh (x)cosh Hyperbolic cosine. Syntax: cosh (x)tanh Hyperbolic tangent. Syntax: tanh (x)








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Defining a Function> In general, to define a function:

1. Enter the function name in the field to the left of the equals sign. Function namesmust start with an alphabetic character, and may include alphanumeric charactersand the underscore. Note that pi is a built-in constant and may not be redefined.

2. Enter the expression for the function in the field to the right of the equals sign.3. Choose Add or press Return.

The function is then listed in the following fields:

4. When you finish adding functions, choose Done.

For further information on the functions and expressions used in the Symbol Table, con-sult the online documentation on the Expression Evaluator.

Changing a Function> To modify an existing function:

1. Select the function.2. Change any variables, operators, intrinsic functions, or other factors.3. Choose Update. The updated function appears in the Symbol Table.

Deleting Functions> To delete an expression:

1. Choose Options/Expressions. The Symbol Table appears.2. Select the expression you wish to delete to highlight it.3. Choose Delete. The expression vanishes.4. Choose Done. The expression is deleted.

Dataset

Choose Dataset to access the Edit Dataset window and create datasets for the solution.Datasets are used in conjunction with piecewise linear functionality to create functions.

Name Displays the name of the function.Value Displays the numeric value of the function (if applicable).Expression Displays the function.








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Options/Default ColorUse this command to change an object’s color or to specify a default color for new objects.

> To set the default color:1. Choose Options/Default Color. The Color window appears:

2. Click on the Current Color square. A palette of colors appears.3. Select the new color. It displays in the color square.4. Optionally, select Make it the default color to define this color as the default color.5. Optionally, select Recolor Selection to recolor the selected objects.6. Choose OK to accept the color or choose Cancel to cancel the color change.

Options/Selection ColorUse this command to edit the colors of selected objects in terms of their RGB intensities.

> To modify the select color:1. Choose Options/Selection Color. The Selection Color window appears.2. Slide the scroll bars to adjust the color in the color pool or enter the values in the

Red, Green, and Blue fields at the bottom of the scroll bars.3. Choose OK to accept this color or choose Cancel to cancel the color change.








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Options/PreferencesUse this command to specify your default 3D Modeler or 3D Post Processor preferencesfor new projects. This command allows you to set:

• The number of views on the screen.• The shading of the default display of your model.• Any macros you wish to execute upon starting a new model.• The default units and selection color of your model.• The type of grid and grid size used in your model.• The save format of the model (binary or ascii).

Any preferences you set remain as the default settings for all future models.

> To set any of these preferences:1. Choose Options/Preferences. The following window appears:

2. Enter the Number of Views you wish to see when you open a new project in the3D Modeler. The default is set to four, which covers all major axes and one 3Dview.

3. Select a Default view from the pull-down menu. This determines the shading ofyour model.

4. Select a style of Coordinate system from the pull-down menu.








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5. Select a default Units setting from the pull-down menu.6. Select the Grid type from the pull-down menu.7. Enter the Auto adjust grid size. You can toggle this setting to turn it off.8. Select Display units selection dialog for new projects to turn on the units

selection dialog box for new projects.9. Select Display reminder for recording macro to display a reminder dialog box on

startup when you create macros.10.Select Check overlap on save to automatically check overlap when saving.11.Select Save in binary format to switch the save format between ascii and binary.12.Enter any macros you wish to execute on startup in the Startup macro field.13.Click on the Default color square to choose a new default color.14.Click on the Selection color square to choose a new color for selected items.15.Choose Revert to defaults if you wish to erase your settings.16.Choose OK to accept the new defaults or choose Cancel to cancel the defaults

you specified.

Your preferences are now specified. The project changes to suit the new settings.

3D Post Processor Preferences

If you choose this command from the 3D Post Processor, a window appears, allowing youto define the settings for plot lighting, and colorkey colors.

> To define the post processor preferences:1. Choose Options/Preferences. The 3D Post Processor Preferences window

appears.2. Optionally, select Plot lighting to turn on a light source in the display. When you

display a model, an imaginary light source is projected on the objects. As you turnor rotate the model, the colors on the objects will change. When you turn the lightsource off, the colors remain the same no matter which direction you rotate theobject.

3. Enter the Number of displayed colorkey colors. By default, this is set to 25. Thisfield dictates the maximum number of colors displayed in the color key, regardlessof the number of divisions in the plot.

4. Choose OK to accept the settings or Cancel to ignore them and return to the 3DPost Processor.





3D Post Processor Pref-erences


Maxwell 3D — Window MenuTopics:

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Window MenuWindow CommandsWindow/NewWindow/CloseWindow/TileWindow/Cascade

Window MenuUse the commands on the Window menu to:

• Create new windows.• Close view windows.• Tile and cascade view windows.

When you choose Window from the menu bar, the following menu appears:

Window CommandsThe commands on the Window menu are:

New Creates a new 3D view window.Close Closes the active view window.Tile Moves and resizes windows to display them all on the screen at the

same time.Cascade Stacks (“cascades”) windows, starting at the upper left corner of the

project window.



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Window/NewUse this command to create a new view window.

> To create a new view window:• Choose Window/New.

A new window appears on the screen and automatically becomes the active window. Thenew window displays the yz-plane by default.

You can create as many windows as you like. Each window’s coordinate system, grid, andviewing area are set independently.

In the 3D Modeler, objects drawn in one window are displayed in the other windows thatinclude the item’s location in their field of view. You can also begin drawing an object inone window and complete the object in another.

Window/CloseUse this command to close the active view window.

> To close a view window:1. Select a window to make it the active one.2. Choose Window/Close. The view window disappears.

The geometric model is not deleted if you close view windows. To display the modelagain, open a new window or exit the module and re-enter it.

Window/TileUse this command to move and resize view windows so that they are visible on thescreen at the same time. This command is used to organize your windows so that you cansee exactly what each window is displaying at any given time. This tile form is the defaultsetting of the 3D Modeler.

> To tile the view windows:• Choose Window/Tile.

All open windows appear on the screen at the same time.




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Window/CascadeUse this command to move and resize the windows so that they are stacked on top ofeach other.

> To cascade your view windows:• Choose Window/Cascade.

All open windows are displayed in a stack on the screen, with the active view window ontop of all other view windows.



Maxwell 3D — Help MenuTopics:

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Help MenuUse the commands on the Help menu to:

• Access information on the commands of the current module.• Access information on the current module you are in.• Access information on the online help system and documentation.• Access the table of contents and index of the online documentation.• Access the online tutorial.• Learn about the hotkeys.

When you choose Help, a menu similar to the following one appears. Each menu isdependent upon its module and varies accordingly. For example, this menu is particular tothe modeler:



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Help CommandsThe commands in the Help menu are:

Not all of these commands are present in all modules.

Help/About HelpUse this command to learn how to use the features of the online documentation, such asthe scroll buttons, the menu commands, and the hyperlinked commands.

> To find out information on how to use the online documentation:• Choose Help/About Help.

The information on how to use the online documentation appears.

Help/On ModuleUse this command to learn about the current module you are in. For example, if you are inthe 3D Modeler, this command will read Help/On 3D Modeler. Choosing this will take youto the online documentation on the modeler. Similarly, if you are in the Post Processor, thecommand will read Help/On Post Processor. Accessing it will take you to the first pageof the documentation on the Post Processor.

> To access the documentation for the current module:• Choose Help/On Module.

The documentation on the current module appears.

About Help Provides help on the online help system.On Module Provides an overview of the current module.On Maxwell 3D Accesses the first page of the online documentation.On Context Provides help on the commands of the Maxwell 3D.Contents Accesses the table of contents for the online documentation.Index Accesses the index for the online help system.Tutorial 3D Modeler. Accesses the online tutorial for the 3D Modeler.Shortcuts Provides a list of hotkeys and the uses of tool bars.





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Help/On Maxwell 3DUse this command to get a description of Maxwell 3D, its features, functions, and uses.This command takes you to the first page of the online documentation.

> To access the online documentation:• Choose Help/On Maxwell 3D.

The first page of the online documentation appears.

Help/On ContextUse this command to access help on the command you have chosen.

> To access help on a particular command or user-interface item:1. Choose Help/On Context. A cursor with a question mark appears.2. Select the menu item, icon, or portion of the screen on which you wish to access

the online documentation.

A help screen appears, displaying pertinent information on the item you have chosen. Ifno documentation is available on the item you have chosen, a window appears, explainingthe error.

Help/ContentsUse this command to access the table of contents. The table of contents is organized bymodule in the sequence in which you are expected to use the modules.

> To access the table of contents:• Choose Help/Contents.

The table of contents appears.





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Index

Help/IndexUse this command to access the index. The index lists all headings, commands, and top-ics covered in the online documentation.

> To access the index:• Choose Help/Index.

The index appears.

Help/Tutorial3D Modeler

Choose this command to access the online tutorial on the 3D Modeler. The tutorial givesexamples of how to draw various objects in the 3D Modeler.

Help/ShortcutsUse this command to get a list of hotkeys or uses of the tool bars. These allow you to exe-cute commands much faster than by using the commands in the menu bar.

Help/Shortcuts/Hotkeys

Hotkeys are keystrokes designed to execute commonly used viewing and exiting com-mands. These appear beside their respective commands in the pull-down menus. Clickhere for a list of the more commonly used hotkeys.

Help/Shortcuts/Tool Bar

Tool bars are a list of icons that allow you to execute commonly used commands withoutthe need to pull down the menus. Each module has a different tool bar.

To execute a tool bar command, click on the icon of that command. To see an explanationof the icon command, click on the icon and hold down the left mouse button.

Hotkeys Lists and explains the hotkeys.Tool Bar Explains the uses of tool bars.




Maxwell 3D — Material ManagerTopics:

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Material ManagerSelect Setup Materials to do the following:

• Specify the material attributes for objects by assigning materials from the globaldatabase to them.

• Create new materials and add them to the local database. You can define newmaterials, or derive them from existing materials.

When you choose Setup Materials, the following window appears:

If you are setting up an electrostatic problem, the following message appears:

Note: All materials with a conductivity greater than 10000siemens/meter will be treated as perfect conductors.

This is useful to remember because you can make an object a perfect conductor ratherthan spend time deriving a material with a high conductivity.

Material ManagerModifying the Material SetupAssigning MaterialsMaterial DatabaseAdding Materials to theDatabase

Assigning Materials toObjects

Excluded ObjectsChanging Material AttributesDeleting MaterialsMaterial AttributesSelecting Several Objects atOnce

Deselecting ObjectsHelp Menu



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Modifying the Material SetupIf you select Setup Materials after generating a solution, the following message appears:

If you make changes to the material assignments and save thosechanges, all solution data will be deleted and will have to berecomputed. Pick “View Only” if no changes are to be saved,“Modify” if changes are to be saved or “Cancel” to cancel thisoperation.

> Do one of the following:• Choose View Only to access the Material Manager in view-only mode. You can view

(but not change) all material assignments.• Choose Modify to change the existing material assignments. If you modify and save

any material assignments, you must solve the problem again. All solution data aredeleted.

• Choose Cancel to abort the command and return to the Executive Commandswindow.

Material ManagerModifying the MaterialSetup

Assigning MaterialsMaterial DatabaseAdding Materials to theDatabase






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Assigning MaterialsAll objects in the model must be assigned a material. When you assign a material to anobject, the properties associated with the material — such as relative permeability, rela-tive permittivity, conductivity, and so forth — are assigned to the object. Only one object,background, is assigned a default material (vacuum). The background represents thespace surrounding the model — that is, the area of your model that is not contained withinany closed geometric objects.

To set up a valid model in Maxwell 3D, you must assign a material to all “unassigned” 3Dobjects in the model.

> Assigning materials is a two-step process.1. If they are not already included in the material database, add all the materials you

will need as described in the Adding Materials to the Database section.2. Assign a database material to each object in the model as described in the

Assigning Materials to Objects section.

For example, to assign polyamide as the material for the object substrate, first addpolyamide to the material database and then assign the material polyamide to the objectsubstrate.







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Material DatabaseThe material database consists of a group of predefined materials that may be assignedto individual objects in a model.

Global Material Database

The global material database is the primary material database used throughout all Max-well software. Materials from the global database can only be deleted or modified fromthe Maxwell Control Panel, not from Material Manager. These are listed as Externalmaterials in the materials list displayed in the lower left corner of the screen.

Local Material Database

The local material database is a copy of the global material database supplied with theMaxwell 3D. You can add new materials to a project’s local database. Materials added toa local database can be deleted or modified. However, they cannot be accessed by otherprojects and are flagged as Local materials in the display list. Any Local or Externalmaterial in a project’s material database may be assigned to objects in its model.

Inheritance

New materials can be “derived” from any existing material in the database, allowing you tocreate a family of materials that share, or inherit, several characteristics of the base mate-rial. You can then modify the characteristics of the derived materials as necessary.

One advantage to deriving materials is that you can change the common characteristicsof all materials in the family simply by changing the characteristics of the base material. Inaddition, it makes accessing material data faster and helps to eliminate redundancies inrelated materials.

Material ManagerModifying the Material SetupAssigning MaterialsMaterial Database

Global Material Data-base

Local Material DatabaseInheritance

Adding Materials to theDatabase






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Adding Materials to the Database> If the materials you want to use are not in the project’s material database, add them as

follows:1. Do one of the following:

• To create a new material, choose Material/Add.• To create a material whose characteristics are derived from an existing material:

a. Select a material in the Materials list box.b. Choose Material/Derive.

2. Enter a new name for the material.

3. If appropriate, select one of the following material types:

4. Enter the material’s properties in the Material Attributes fields.• For perfect conductors, the material’s conductivity is automatically set to infinity.

This material properties can be changed in perfect conductors.• For anisotropic materials, specify the major diagonals of the material’s anisotropy

tensors as described under Anisotropic Materials.• For nonlinear materials, a button labeled BH Curve replaces the Rel.

Permeability field. You must define a BH-curve to specify the relativepermeability.

• For permanent magnets, you must specify a non-zero value for the coercivity orthe retentivity.

5. After all material characteristics have been set, choose Enter.

The new material now appears in the Materials list box and can be assigned to objects.

Note: The stem word Material is reserved for use as the default name of new mate-rials. It cannot be assigned as a material name.

Perfect Conductor A perfectly conducting material.Anisotropic Material A material whose properties vary with direction.Nonlinear Material (Magnetostatic.) A material with a nonlinear relative perme-

ability, which must be specified using a BH curve.







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Assigning Materials to ObjectsAfter any materials are added to the project’s material database, you can assign them toobjects.

> To assign materials to objects:1. Select the objects to be assigned a material by doing one of the following:

• Select the name of an object from the Objects list box displayed on the left side ofthe screen.

• Click the left mouse button on an object in the display window. The object and itsname are both highlighted.

• To select multiple objects, follow the procedure under Selecting Several Objects atOnce. Note that the procedure for selecting objects on the PC version of Maxwell3D is different from that of the Workstation version. See Variations in ScreenDisplays and Commands for details.

2. Select the name of the material to assign to the object. Its characteristics aredisplayed in the Material Attributes box at the bottom of the Material Managerwindow.

3. With both the object name(s) and material name highlighted, choose Assign.4. If a material with vector, anisotropic, or functional properties is assigned to an

object, the window on the following page appears. Specify the tensor or functionorientation or the vector direction, following the procedure under Functional andVector Material Properties. The default orientation for the material aligns it with the

Material ManagerModifying the Material SetupAssigning MaterialsMaterial DatabaseAdding Materials to the Data-base


Functional and VectorMaterial Properties





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x-axis of the global coordinate system.

Repeat this procedure to assign a material to every object in the model. Maxwell 3D willnot allow you to continue setting up your model until all objects have been assigned mate-rials.








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Functional and Vector Material Properties

The properties of some materials vary in magnitude according to the position inside anobject. For instance, conductivity and relative permeability could vary if there is a densitygradient across the object. Other material properties vary in direction according to theposition inside an object. For instance, the magnetization vector of some permanent mag-nets varies in direction at different points inside the magnet. Such material propertiesmust be defined as functions.

In addition, functional material properties can be used to define a material propertyaccording to a mathematical expression. If you have purchased parametric analysis capa-bility, material properties that are to be varied during a parametric sweep must be identi-fied as functions.

When you assign a material with vector, anisotropic or functional properties to an object,the menu prompts you to specify the material’s orientation to the object’s local coordinatesystem.

• For functional properties, the system prompts you to specify the material’s orientationto the object’s local coordinate system.

• For vector properties such as magnetization and polarization, the system prompts youto define the vector’s direction. (The fields for specifying an origin do not appear if thevector property has a constant magnitude and direction.)

A local coordinate system is used to evaluate material properties that vary in magnitudeor direction according to their position. By default, the local coordinate system is alignedwith the global xy-coordinate system and has its origin at the center of the object.

> To specify the direction of a material with vector or functional properties:1. Choose Assign. The Assignment Coord. Sys. window appears.2. Assign the material to the object using the procedure under the Assigning

Materials to Objects section.3. Select one of the following options:

• Align with object’s orientation.• Align relative to object’s orientation.• Align with a given direction.

4. Choose OK to assign the material or choose Cancel to cancel the action.








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Align with Object’s Orientation

This aligns the function or vector with the x-axis of the object’s local coordinate system.

The need for an orientation specific direction arises when one desires to assign objectswith anisotropic material properties. This means that a material behaves differently in onedirection (orthogonal) than in another. Maxwell 3D differentiates anisotropic materials intotwo categories: permanent magnets and “other.”

For permanent magnets, you must define the anisotropic axis, or preferred magnetizationdirection. This direction is defined to be where the x-axis itself points. For any other aniso-tropic material, you define the behavior of the material in any or all of the axes.

> If you selected with object’s orientation:• Choose OK to accept the alignment.

The About X (roll), About Y (pitch), and About Z (yaw) fields remain inactive.








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Align Relative to Object’s Orientation

This option aligns the function relative to the objects’s orientation.

> If you selected relative to object’s orientation (the default):1. For magnetostatic problems, select the Relative Orientation from the ordering

pull-down menu. This function only affects the permanent magnetization in the x, y,and z directions.

2. Enter the Relative Orientation (in degrees) of the vector or function in the AboutX, About Y, and About Z fields. These are defined as follows:• About X (Roll) — the rotation of the vector or function about the x-axis. Currently,

the roll angle has no impact on permanent magnets, though it rotates the y and z-tensors of other anisotropic materials about the x-axis.

• About Y (Pitch) — the rotation of the vector or function about the y-axis. Currently,the pitch angle rotates the x-axis (and thus the object’s orientation) within the xz-plane. A positive angle will move the x-axis in the negative z direction. Likewise, anegative angle will move the x-axis in the positive z direction.

• About Z (Yaw) — the rotation of the vector or function about the z-axis. Currently,the yaw angle rotates the x-axis (and thus the object’s orientation) within the xy-plane.

This concept is illustrated below. In the first panel, the tensor is rotated α degreesabout the x-axis. In the second panel, a tensor is rotated β degrees about the y-axis. In the third panel, a tensor is rotated γ degrees about the z-axis. The resultingtensor has the coordinate system relative to the fixed coordinate system.

3. Choose OK to accept these values or Cancel to ignore the values.

y

y’

α

z’z

y

x x

z

y

xRoll Pitch Yaw

z

β

z’ x’

y’

x’

γ








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Align with a Given Direction

Aligns the function at an angle to the object’s global coordinate system. This lets youspecify the direction in which an anisotropic or vector material property points, or define afunctional material property that acts at an angle to the global coordinate system.

> If you selected with a given direction:1. For permanent magnets, select the order of enforcement from the ordering pull-

down menu. This controls the order in which the angles are evaluated for thematerial assignment. This only affects magnetization.

2. Enter the angles of About X, About Y, and About Z (in degrees) of the vector orfunction in the Global Orientation fields. You must select the buttons below eachfield to specify which values are functions. If you specify any values as functions,you must then enter the origin in the Global Origin field.

3. If necessary, choose Reset to reset the values of the field and re-enter the values.4. If a material with functional properties is being assigned, enter the coordinates of

the new global origin for the function in the X, Y, and Z fields.5. Choose OK to accept the values or Cancel to cancel them.








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Excluded ObjectsIn some cases, you must exclude the background from the model. The Maxwell 3D willnot solve for the electric and magnetic fields in an excluded object, making it theoreticallynon-existent.

Exclude the background when you plan to use the outside edges of objects as the out-side boundaries of the model. Do this when you want to take advantage of symmetry andmodel only part of a symmetrical structure. One requirement for this is that the objectedges that will be matching boundaries must lie at the outside edges of the model.

Excluding and Including Background Objects

Above the Objects list box is a button that toggles between Include and Exclude.Exclude is enabled only when the background object is selected.

> To exclude or include the background object:1. Select the background object.2. Select Exclude to ignore an object in field solutions. Select Include to include an

object in the field solutions.







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Changing Material Attributes> To change the attributes associated with a material in the project’s local material

database:1. Select the appropriate Local material in the Material list box. The attributes of the

selected material appear in the Material Attributes box.

2. Optionally, change the type of material as described in the Adding Materials to theDatabase section.

3. Modify the appropriate material characteristics. Refer to Material Attributes for adescription of material attributes.• If the material is anisotropic, see Anisotropic Materials for instructions on changing

the material’s attributes.• If the material is nonlinear, see Nonlinear Materials for instructions on how to

modify its BH-curve.• If the material has functional properties, see Functional Material Properties for

instructions on how to modify functions and change whether the materialproperties are functional or not.

4. To delete the changes and revert back to the material’s original properties, chooseRevert.

5. Choose Enter to save the new characteristics for the selected material.

Underiving and Rederiving Materials

Any derived materials can be underived and modified.

> To underive a material:1. Select the derived material from the materials list.2. Choose Material/Underive. The material characteristic fields below the view

window become active.3. Enter any new values in the material characteristics fields.4. Do one of the following:

• Choose Enter to accept the new derived material characteristics.• Choose Revert to ignore any changes to the derived material.

Note: You cannot modify the properties of materials in the global database. Thesematerials are labeled as External (lock) in the Material list box.



Excluded ObjectsChanging MaterialAttributes

Deleting MaterialsMaterial AttributesSelecting Several Objects atOnce




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Deleting Materials> To delete a material from the local material database:

1. Select the Local material you wish to delete.2. Choose Material. A menu appears.3. Choose Clear.

The material is deleted.

Deleting Derived Materials

If you delete a material, any materials that have been derived from it will be listed asUnderived in the Material Attributes box. They will, however, retain the common charac-teristics of the deleted material.







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Material AttributesUse the following fields to describe the electromagnetic properties of a linear, isotropicmaterial. Although all of the properties listed below apply to a material, the specific prop-erties that appear in the Material Manager window depend on which field solver anddrawing type were selected for a model. The solvers and model types that require a par-ticular material property to be specified are listed under that material property.

Relative PermittivityElectrostatic, Eddy Current

Enter the relative permittivity (the dielectric constant) of a material, εr, in the Rel. Permit-tivity(Eps) field.

The relative permittivity is a dimensionless number.

Relative PermeabilityMagnetostatic, Eddy Current

Enter the relative permeability of a material, µr, in the field Rel. Permeability (Mu).

The relative permeability is a dimensionless number.

Note: Only two material properties at a time may be specified for electrostatic andmagnetostatic models. The other properties are computed from these edit-able properties. Use the Options command to identify which two propertiesmay be entered. See Dependent and Independent (Editable) Material Prop-erties for details.



Excluded ObjectsChanging Material AttributesDeleting MaterialsMaterial Attributes

Relative PermittivityRelative PermeabilityConductivityImaginary PermeabilityMagnetic CoercivityMagnetic Retentivity

Selecting Several Objects atOnce




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ConductivityElectrostatic, Eddy Current

Enter the conductivity of a material, σ, in the Conductivity field.

Conductivity is entered in siemens/meter.

Depending on which field solver you selected for the model, objects are treated differentlybased on their conductivity.

• No conduction currents can flow in perfectly insulating materials.• All materials whose conductivity is above 10,000 siemens/meter will be treated as

perfect conductors in electrostatic problems.

No field solution will be computed inside objects that are assigned these materials.

Warning: Electrostatic field solutions may fail to converge if materials with relativelylow conductivities are used as charge or voltage sources in a model.




Relative PermittivityRelative PermeabilityConductivityImaginary PermeabilityMagnetic CoercivityMagnetic RetentivityMagnetization





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Imaginary Permeability

Eddy Current

Some materials exhibit a permeability that includes both a real and imaginary component.The imaginary component is used to model magnetic losses in a time-varying field usingthe relationship:

where:

• µ’r is the real component of the relative permeability.

• µ”ris the imaginary component of the relative permeability.

As shown below, a complex relative permeability causes the B-field to lag behind the H-field — similar to the behavior of a nonlinear, lossy material. The power loss during thiscycle (the pink area) is approximately equal to the hysteresis loss (the area within the bluelines). The hysteresis curve for a material with a constant, real permeability (the straightyellow line) is shown as a reference.

Enter the imaginary relative permeability of a material, , in the Imag. Permeabilityfield. The default imaginary permeability of zero is that of a material that exhibits no mag-netic loss in a time-varying field.

B µ′( j µ″r( )– )µoH=

B

H

Constant, complex µr

Constant, real µrNonlinear µr

(Hysteresis curve)

µ″ r









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Magnetic CoercivityMagnetostatic

Enter the value of a material’s magnetic coercivity, Hc, in the Magnetic Coercivity field. Ina linear, permanently magnetized material, the magnetic coercivity is equal to the value ofH needed to reduce B to zero:

This relationship is shown graphically on the left side of the figure below.

Magnetic coercivity is entered in amperes/meter. The default coercivity, zero, is that of amaterial that is not permanently magnetized. To define a linear permanent magnet, entera non-zero value for Hc.

B µoµr H Hc+( )=

MagnetostaticB

HHc

MagneticCoercivity

BrMagnetic

Remanence

Permeability

D

EEc

ElectricCoercivity

DrElectric

Retentivity

Electrostatic

PermittivityµBr

Hc------= ε

Dr

Ec------=









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Magnetic RetentivityMagnetostatic

Enter the value of a material’s magnetic retentivity (or remanence), Br, in the MagneticRetentivity field. The magnetic retentivity gives the level of permanent magnetization in amaterial. In physical terms, it is equal to the magnetic flux density, B, that remains in amaterial when the magnetic field, H, drops to zero — as shown on the left side of the fig-ure above.

Magnetic retentivity is entered in teslas. The default retentivity, zero, is that of a materialthat is not permanently magnetized. To define a linear permanent magnet, enter a non-zero value for Br.

MagnetizationMagnetostatic

Enter the value of a material’s magnetization, Mp, in the Magnetization field. The magne-tization is a vector representing the magnetic moment per unit volume of the material. It isrelated to the magnetic field and magnetic flux density by:

Magnetization is entered in amperes/meter.

To define a permanently magnetized material, enter a non-zero value for Mp. The direc-tion of the magnetization vector is specified when you assign the material to the object —as described in the Functional and Vector Material Properties section. Enter the angle ofthe magnetization vector from the global x-axis in the Angle field.

To define a material whose magnetization varies in direction, use the Options commandto identify magnetization as a Vector Function. Then, use the Vector Fn button (whichappears next to Magnetization) to select which type of magnetization vector is defined.See Vector Functions for details.

B µo µrH M p+( )=









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Selecting Several Objects at OnceIf more than one object is made of a particular material, select several objects at onceusing one of the following methods:

> Use the mouse to select several objects as follows:1. Choose Multiple Select.2. Click the left mouse button on each object or object name.

> Use the Select commands as follows:• Choose Select from the selection box. Do one of the following:

• Choose By Name to select objects that have the same first letter or some othercharacteristic of their names in common. The following field appears:

Enter object name/regular expression

Using asterisks as a wildcard characters, enter an expression that identifies theobjects you wish to select. For example, to select all objects that begin with theletter c, enter c*.

• Choose All Objects to select all objects.

The names of all selected objects are highlighted. After the objects are selected, followthe steps under Assigning Materials to Objects to assign a material to the selectedobjects.

Deselecting Objects> To deselect selected objects:

• To deselect a single selected object or group of objects, simply click on the object orgroup’s name in the list.

• To deselect all selected objects and groups, choose Deselect. The objects aredeselected and their names are no longer highlighted.

Help MenuChoose Help from the lower left corner of the Material Manager window to access theonline documentation on the Material Manager, Maxwell 3D, and other features of thesoftware.



Excluded ObjectsChanging Material AttributesDeleting MaterialsMaterial AttributesSelecting Several Objectsat Once




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Perfect ConductorsAll solvers

Choose Perfect Conductor to define a perfectly conducting material — that is, a materialwhose conductivity is infinite. No field solution is performed inside a perfect conductor.Instead, the Maxwell 3D treats the conductor as follows:

• In electrostatic problems, all materials with a conductivity above 10,000 siemens/meter are treated as perfect conductors. (For all practical purposes, the solver treatsthese materials as having an “infinite” conductivity.) All charge is distributed on thesurface of an object which cancels out the electric field inside the object.

• In magnetostatic and eddy current problems, all currents in perfect conductors aresurface currents — modeling the behavior of current at very high frequencies wherethe skin depth approaches zero. Magnetic fields cannot penetrate the conductor, andno currents are induced inside it.

If Perfect Conductor is selected, no functional material properties may be defined. TheOptions button is grayed out to indicate this.

Note: Be aware of the following when using perfect conductors in eddy current prob-lems:• In some cases, conductors whose skin depths are very small compared

to a structure’s dimensions can be modeled using impedanceboundaries instead of perfect conductors.

• Do not use a perfect conductor if the skin depth is relatively large (thatis, greater than 1/20 to 1/50 of the model’s dimensions). Instead, assigna regular conductor such as copper to the object, and turn on the eddyeffect in the Boundary/Source Manager. This explicitly tells thesimulator to compute induced currents inside the conductor.

Perfect ConductorsAnisotropic MaterialsPermanent MagnetsNonlinear MaterialsFunctional Material Proper-ties



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Anisotropic MaterialsAll solvers

Some materials exhibit characteristics that vary with direction and need to be defined bydefining their anisotropy tensors. Choose Anisotropic Material to define a material withanisotropic properties.

You must define the three diagonals for anisotropic conductivity, permittivity, permeability,and imaginary permeability. Each diagonal represents a tensor of your model along anaxis.

> To define the diagonals, follow this general procedure:1. Choose Material/Add.2. Select Anisotropic Material from the Material Attributes box.3. Select the property you wish to define.4. If any of the diagonals are functions, choose Options to specify which diagonals

are constant values and which are functions. When you exit this step, anyfunctional diagonals appear as undefined.

5. Select Functions to define your functions.6. Repeat this procedure for each of the properties.7. Enter the name of the material in the Material Attributes box.8. Choose Enter to accept this material.

Perfect ConductorsAnisotropic Materials

Anisotropic PermittivityTensor

Anisotropic PermeabilityTensor

Anisotropic ConductivityTensor

Anisotropic Imaginary Rel-ative Permeability Tensor

Permanent MagnetsNonlinear MaterialsFunctional Material Proper-ties



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Anisotropic Permittivity TensorElectrostatic, Eddy Current

The permittivity tensor for an anisotropic material is described by:

where:

• ε1 is the relative permittivity of the material along one tensor axis.• ε2 is the relative permittivity along the orthogonal tensor axis.• ε3 is the relative permittivity along the third tensor axis.• ε0 is the permittivity of free space.

The relationship between E and D is then:

> To specify the relative permittivity for an anisotropic material:1. Select Permittivity.2. Enter the value of ε1 in the diag[1] field.3. Enter the value of ε2 in the diag[2] field.4. Enter the value of ε3 in the diag[3] field.

If the relative permittivity is the same in all directions, use the same value for ε1, ε2, and ε3.If any of these values are functions, choose Options and select which values are to bedefined as functions. You define the functions by choosing Functions.

εε1ε0 0 0

0 ε2ε0 0

0 0 ε3ε0

=

Dx

Dy

Dz

ε

Ex

Ey

Ez

=









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Anisotropic Permeability TensorMagnetostatic, Eddy Current

The permeability tensor for an anisotropic material is described by:

where:

• µ1 is the relative permeability along one axis of the material’s permeability tensor.• µ2 is the relative permeability along the orthogonal permeability tensor axis.• µ3 is the relative permeability along the third permeability tensor axis.• µ0 is the permeability of free space.

The relationship between B and H is:

> To specify the relative permeability for an anisotropic material,1. Select Permeability.2. Enter the value of µ1 in the diag[1] field.3. Enter the value of µ2 in the diag[2] field.4. Enter the value of µ3 in the diag[3] field.

If the relative permeability is the same in all directions, use the same value for µ1, µ2, andµ3. If any of these values are functions and not constants, you must select which valuesare to be defined as functions. To define the magnetization as a constant or a type offunction, refer to the Options section.

µ[ ]µ1µ0 0 0

0 µ2µ0 0

0 0 µ3µ0

=

Bx

By

Bz

µ

Hx

Hy

Hz

=



Anisotropic Permeabil-ity Tensor






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Anisotropic Conductivity TensorEddy Current

The conductivity tensor for an anisotropic material is described by:

where:

• σ1 is the relative conductivity along one axis of the material’s conductivity tensor.• σ2 is the relative conductivity along the material’s orthogonal conductivity tensor axis.• σ3 is the relative conductivity along the material’s third conductivity tensor axis.

The relationship between J and E is then:

> To specify the conductivity for an anisotropic material:1. Select Conductivity.2. Enter the value of σ1 in the diag[1] field.3. Enter the value of σ2 in the diag[2] field.4. Enter the value of σ3 in the diag[3] field.

The values of σ1 and σ2 apply to axes that lie in the xy cross-section being modeled. Thevalues of σ3 apply to the z component. These values affect current flowing in dielectricsbetween the conductors.

To define the imaginary permeability, refer to the Options section. To define a functionexpression, refer to the Functions section.

σ[ ]σ1 0 0

0 σ2 0

0 0 σ3

=

Jx

Jy

Jz

σ

Ex

Ey

Ez

=




Anisotropic Conductiv-ity Tensor





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Anisotropic Imaginary Relative Permeability TensorEddy Current

The "imaginary permeability" tensor for an anisotropic material is described by:

where

• µ’’1 is the “imaginary relative permeability” in one direction.

• µ’’2 is the “imaginary relative permeability” in the orthogonal direction.

• µ’’3 is the “imaginary relative permeability” in the third direction.

• µ’1, µ’

2, and µ’3 are the relative real permeabilites specified earlier.

• µ0 is the permeability of free space.

The relationship between B and H will then be:

> To specify the imaginary relative permeability for an anisotropic material:1. Select Imag. Permeability.2. Enter the value of µ’’

1 in the diag[1] field.3. Enter the value of µ’’

2 in the diag[2] field.4. Enter the value of µ’’

3 in the diag[3] field.

If the imaginary relative permeability is the same in all directions, use the same value forµ’’

1, µ’’2, and µ’’

3. To define the imaginary permeability as a constant or a type of functions,refer to the Options section. µ’’

1

µ''[ ]µ( '1 jµ''1 )µo– 0 0

0 µ( '2 jµ''2 )µo– 0

0 0 µ'3 jµ''3–( )µ0

=

Bx

By

Bz

µ

Hx

Hy

Hz

=





Anisotropic ImaginaryRelative PermeabilityTensor




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Permanent MagnetsA permanent magnet is defined as a material that generates a magnetic flux due to per-manent magnetic dipoles in that material.

Nonlinear vs. Linear Permanent Magnets

In general, permanent magnets are nonlinear and should be modeled via a BH-curve asshown below. The magnetic coercivity, Hc, is defined as the BH-curve’s H-axis intercept,and the magnetic remanence, Br, as its B-axis intercept.

In many applications, however, the permanent magnet’s behavior can be approximatedusing a linear relationship between B and H. In these cases, there is no need to create anonlinear material. Simply enter the appropriate values of Br or Hc for the material whendefining its properties.

Linear Permanent Magnet

B

H

Br

Hc

Nonlinear Permanent Magnet

Perfect ConductorsAnisotropic MaterialsPermanent Magnets

Nonlinear vs. Linear Per-manent Magnets

Nonlinear MaterialsFunctional Material Proper-ties



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Nonlinear MaterialsMagnetostatic

If a material has a permeability that varies with the flux density, a B vs. H curve (BH-curve) such as the one below is needed to describe the material’s nonlinear behavior.

In nonlinear materials, the B-field (magnetic flux density) is a function of itself:

where µr(B), the relative permeability, depends on the magnitude of the B-field at eachpoint in the material. Therefore, to model the magnetic behavior of the material, a curverelating the B-field directly to the H-field is used to describe the nonlinear relationship.

B µr B( )µoH=

Perfect ConductorsAnisotropic MaterialsPermanent MagnetsNonlinear Materials

Adding Nonlinear Materi-als

Entering a BH-CurveDeleting a BH-CurveModifying B and H valuesfor a BH-Curve

Adding Points to a BH-Curve

Importing a BH-CurveExporting a BH-CurveAxesViewNonlinear PermanentMagnets

Functional Material Proper-ties



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Adding Nonlinear Materials> To add a nonlinear material to the local database for a magnetostatic problem, follow

this general procedure:1. Select Nonlinear Material as the material type.2. Choose BH Curve. The following window appears:

3. Enter a new BH-curve for the material. Alternatively, you can import an existingBH-curve.

4. Choose Exit. A message appears prompting you to save changes.• Choose Yes to save the BH-curve and return to the Material Manager.• Choose No to exit without saving the BH-curve.• Choose Cancel to remain in the BH-curve entry window.

Enter the other material properties as you would normally.


Adding Nonlinear Mate-rials







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Entering a BH-Curve> To enter a BH-curve:

1. Choose Add Point.2. Enter the points on the curve. Do one (or both) of the following:

• To enter points with the mouse, double-click the left mouse button on the points inthe display area. Start at B=0, which is the value of Hc, the magnetic coercivity.

• To enter points with the keyboard, enter the H and B values of each point in the Hand B fields at the bottom of the window:a. Double click the mouse in the H field.b. Enter the H value of the point.c. Press the TAB key to move to the B field.d. Enter the B value of the point.e. Choose Enter or press Return to accept the point.

If you enter a curve whose slope is less than that of the permeability of free space,an error message appears.

3. When you finish entering the curve, double-click the mouse on the last point in thecurve. If you are using keyboard entry, choose Enter or press Return twice.

The system then draws the BH-curve according to the points you specified.

Deleting a BH-Curve> To delete a BH-curve:

• Choose Clear All.

Modifying B and H values for a BH-Curve> To modify the B and H values of the points on a BH-curve:

1. Choose Move Point.2. Select the new control point on the BH-curve. Control points are the squares

marking the input points.3. Move the point to the new coordinates using the mouse, and click the left mouse

button again. (Alternatively, enter the new B and H values of the point in the B andH fields, then choose Enter.)

4. When you are finished moving points, click the right mouse button.



Entering a BH-CurveDeleting a BH-CurveModifying B and H val-ues for a BH-Curve






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Adding Points to a BH-Curve> To add points to a BH-curve:

1. Choose Add Point. The last point in the BH-curve is automatically selected.2. Specify the B and H values of additional points on the curve using the mouse or

the keyboard as described under Entering a BH-Curve.3. When you finish entering the curve, double click the mouse on the last point in the

curve. If you are using keyboard entry, choose Enter or press Return twice.

The system redraws the BH-curve, adding the new points.

Importing a BH-Curve> To read a BH-curve from a file:

1. Choose Import. A pop-up window appears.2. Enter the directory path name of the BH-curve.3. Select the BH-curve file type (.bh format or .dat format).4. Choose OK.

Exporting a BH-Curve

After you have created the BH-curve for your material, you can export it to other projects.

> To save a BH-curve to a file:1. Choose Export. A pop-up window appears.2. Enter the directory path name of the BH-curve in the File Name field. Alternatively,

use the file folder icon as described under Importing a BH-Curve to locate thedirectory where you want to store the file.

3. Select the BH-curve file type (.bh format or .dat format).4. Choose OK.

Note: BH-curves created in both the previous and present versions of the Maxwell3D can be imported for use in the current version of the software.









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Axes

Use these fields to modify how the axes for entering and displaying BH-curves are dis-played, and to select the units in which the BH-curve is entered.

Minimum Enter the minimum values to be displayed on the B and H axes.Maximum Enter the maximum B and H values to be displayed on the axes.Intercept View-only field showing the B and H values at the point where the

BH-curve intersects the B axis. The H value represents the mate-rial’s magnetic coercivity, Hc, and the B value represents its mag-netic retentivity, Br.

ampere/meter,oersted

Lets you select the units in which H values are entered and dis-played. Click the left mouse button on this field to display a menu ofunits. H values may be entered in ampere/meter (the default) oroersted.

tesla,gauss

Lets you select the units in which B values are entered and dis-played. Click the left mouse button on this field to display a menu ofunits. B values may be entered in tesla (the default) or gauss.

Accept Accepts the new axes settings and units.Cancel Cancels the new axes settings and units, reverting to the previous

settings.Round Off Rounds off the minimum and maximum B and H values to better dis-

play the BH-curve.









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View

Choose View to view the entire BH-curve. A graph of the BH-curve similar to the oneshown below is displayed. Three new buttons appear beneath the view window:

Nonlinear Permanent Magnets

A ferromagnetic material exhibits an overall constructive response as a function of theinfluences that it experiences. One can supply a magnetic field to a volume containing aferromagnetic material, and the overall magnetic field in that volume will be larger than themagnetic field supplied. This physics relationship is represented by:

where:

• B is the total magnetic field.• H is the supplied field.• M is the response of the material to the supplied field.

These are vectorial references, and it is not necessary for B, H, and M to all be aligned ina parallel direction.

One subclass of ferromagnetic materials is the permanent magnet subclass. The materi-als are unique in that they ‘store’ part of the supplied magnetic field in the form of energy.This storage of magnetic energy is represented by how the material behaves in what is

Show Coords Displays the B and H-coordinates of the points you click on.Plot Set Specifies axis scales, tick marks, labels, plot headings, minimum

and maximum B and H values to be plotted, and whether a plot leg-end and axes are displayed.

Graph Set Specifies the color, line thickness, line style, name, and marker typeof the BH-curve. Also specifies whether the curve is visible on theplot. If you do not choose to show the markers or the line, the curveis not displayed on the plot.

Note: You cannot make changes to the BH-curve while viewing a graph of it. Toedit the BH-curve, choose Edit Curve.

B µ0H µ0M+( )=









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called the second quadrant of the hysteresis curve. In general, this curve is nonlinear innature in the second quadrant. A large majority of permanent magnet materials are actu-ally linear in the second quadrant, and this allows us to more easily compute and providethe appropriate physics within a device where they are used. Additionally, a full range ofoperating conditions can be determined readily, where reluctance and variations in sup-plied fields can be taken into account.

When the material is actually nonlinear in the second quadrant, the material behavior is afunction of history, and of the overall supplied fields throughout the volume of the material.To correctly model a nonlinear permanent magnet, one would have to maintain a full his-tory of the supplied fields and determine multiple recoil minor loop characteristics from theoriginal nonlinear curve. Each of these new characteristic curves depends upon the localamplitude and direction of the supplied field, as well as the overall reluctance.

Figure A depicts a nonlinear material with a particular shape and overall reluctance. Fig-ure B shows the same material type with a different shape. Note the difference in theoperating points associated with the geometry alone.

A B









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In general, one cannot consider the appropriate handling of this type of material whenusing the formulations and assumptions associated within a magnetostatic solution. Thesoftware interpolates along the nonlinear curve to determine static operating conditionsfor the magnetic materials in question, and this provides an appropriate solution undertwo very significant conditions.

In Air Demagnetization

If a nonlinear permanent magnet is ‘charged’ or energized in a magnetizing fixture, thenremoved from the fixture, the material will demagnetize itself based on its geometric pro-portions. This behavior will traverse along the second quadrant nonlinear curve. Maxwellwill provide the correct operating point.

In Device Demagnetization

If one assembles a device with a nonlinear permanent magnet in a non-energized condi-tion, and then magnetizes the magnet in the assembly the magnet will demagnetize itselfbased on its geometric proportions as well as taking into consideration the additional pas-sive components in the assembly. This is generally the preferred manner to handle nonlin-ear permanent magnet assemblies as it allows for a larger amount of energy to be stored,then used in assembly operation.

Other Device Considerations

Under all additional operating conditions the appropriate operating point and thus magne-tization character of the nonlinear permanent magnet will be incorrectly handled. Thismeans that permanent magnet devices, which rely on history, or on additionally suppliedfields acting near or on the permanent magnets, will not be computed correctly by a singlemagnetostatic solution.

In these cases, you can sequentially iterate from one solution to another to create apseudo-history simulation, and derive the correct results.









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Functional Material PropertiesAny material property that can be specified by entering a constant can also be specifiedusing a mathematical function, which you can define. Functional material properties canbe used to:

• Define material properties that vary in magnitude according to their position inside anobject.

• Define material properties whose value is given by a mathematical relationship — forinstance, one relating it to another property’s value.

• If you have purchased the 3D Parametrics module, define properties with values thatvary during a parametric sweep. These properties are set to constant functionalvalues.

> In general, to define a functional material property:1. Add or derive a Local material as described in the Adding Materials to the

Database section.2. Choose Options to specify which material properties are constant and which are

functional.3. Choose Functions to define math functions that describe the material property’s

behavior.4. Enter the appropriate function name as the value for the material property.

Perfect ConductorsAnisotropic MaterialsPermanent MagnetsNonlinear MaterialsFunctional Material Prop-erties

OptionsDependent and Indepen-dent (Editable) MaterialProperties

FunctionsVector FunctionsRadial Vector FunctionsTangential Vector Func-tions



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Options

Choose Options to do the following:

• Identify which material properties vary as functions and which remain constant.• For magnetostatic or electrostatic problems, select which two material properties may

be entered, and which two are computed from them.

For each material property, select one of the following:

• Constant. The material property’s value is constant throughout an object (the default).• Functional. The material property’s value is a function.

• For scalar material properties such as relative permittivity, relative permeability,and conductivity, the function defines the value of the material property at allpoints.

• For vector material properties such as polarization and magnetization, the functiondefines the magnitude of the vector at all points. Its direction is constant and isdefined when you assign the material to an object.

• Vector Fn. If a material property (such as magnetization) is a vector, specify whetherits direction and magnitude are constant or are a function of position. This option alsoallows you to define radial and tangential vector material properties such as tangentialmagnetization in a material.

Dependent and Independent (Editable) Material Properties

In magnetostatic and electrostatic problems, only two of the four available material prop-erties need to be specified. The values of the other two properties are dependent onthese properties, and can be computed from the two you enter. This prevents you fromover-specifying a material’s properties.

Use the Options command to pick the properties you would like to enter for a material. Toselect an editable property, click on the select button next to the property.






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Magnetostatic Properties

In magnetostatic problems, select two of the following:

These properties are related by:

where:

• B is the magnetic flux density.• H is the magnetic field.• µ0 is the permeability of free space, 4π×10-7 webers/ampere-meter.• µr is the relative permeability.• Hc is the magnetic coercivity.• Mp is the permanent dipole magnetization.• χm is the magnetic susceptibility.

The magnetic retentivity, Br, represents the value of B in a material when H goes to zero.These relationships then reduce to:

Thus, only two quantities are needed to specify the magnetic properties of the material.The other two can be obtained using this relationship.

Mu The relative permeability, µr.Hc The magnetic coercivity, Hc.Br The magnetic retentivity, Br.Mp The permanent dipole magnetization, Mp.

B µo 1 χm+( )H M p+( ) µo µrH M p+( )= =

B µoµr H Hc+( )=

Br µoM p µoµrHc= =






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Electrostatic Properties

In electrostatic problems, enter the following:

• the Relative Permittivity in Eps units.• the Conductivity in siemens/meter.

Relative Permittivity

Enter the relative permittivity (the dielectric constant) of a material, εr, in the Rel. Permit-tivity(Eps) field.

The relative permittivity is a dimensionless number.

Conductivity

Enter the conductivity of a material, σ, in the Conductivity field. Conductivity is entered insiemens/meter.

Depending on which field solver you selected for the model, objects are treated differentlybased on their conductivity.

• Perfectly insulating materials (materials whose conductivity is zero) will automaticallybe excluded from DC conduction field solutions. No conduction currents can flow inthese materials.

• All materials whose conductivity is above 10,000 siemens/meter will be treated asperfect conductors in electrostatic and AC conduction solutions.

No field solution will be computed inside objects that are assigned these materials.

Warning: Electrostatic field solutions may fail to converge if materials with relativelylow conductivities are used as charge or voltage sources in a model.






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Functions

Choose Functions to define mathematical functions that give a material property’s value.The following window appears:

> In general, to define a function:1. Enter the function name in the field to the left of the equals sign.2. Optionally, choose Datasets to define an expression based on a piecewise linear

construction.3. Enter the expression for the function in the field to the right of the equals sign.

4. Choose Add or press Return.

The function is then listed in the following fields:

5. When you finish adding functions, choose Done.

Note: The predefined variables X, Y, Z, PHI, THETA, and R must be entered incapital letters. X, Y, and Z are the axes. PHI is the angle between the X andY axes. THETA is the angle between the Y and Z axes. R is the distancefrom the origin.

Name Displays the name of the function.Value Displays the numeric value of the function (if applicable).Expression Displays the function.






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Modifying a Function> To modify an existing function:

1. Select the function.2. Change any variables, operators, intrinsic functions, or other factors.3. Choose Update.

The updated function appears.

Deleting a Function> To delete a function:

1. Select the function you wish to delete.2. Choose Delete.

The selected function is deleted.

Vector Functions

Choose Vector Fn to identify whether the direction and magnitude of vector materialproperties (such as magnetization) are constant or functional. Use this option to definevector properties in which the magnitude and the direction of one or more components ofthe vector property:

• Vary as a function of position• Are parametric• Depend on other properties

The Magnetization pop-up window appears when you choose Vector Fn.

> To define a vector function:1. If the values for the x-, y-, or z-components of the vector are constants, enter the

value in the X Component, Y Component, and Z Component fields.2. If the value of an x-, y-, or z-component is functional, choose the Function button

to the right of each field, and enter the function name in the X Component, YComponent, or Z Component fields. If you do not specify a function or value, theword UNDEFINED appears in the component field.

A “generic” vector is defined by its x-, y-, and z-components. The direction in which itpoints depends on whether you have specified constant or functional values for the com-ponents. If they are constant, the vector points in a uniform direction. The magnetizationvector, M, below, varies in both magnitude and direction according to the relationship

Perfect ConductorsAnisotropic MaterialsPermanent MagnetsNonlinear MaterialsFunctional Material Proper-ties





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Mx=X, My=Y, and Mz=Z.

Enter the x-, y-, and z-components and define whether they are functional or constant.The orientation of the vector with the model’s coordinate system is defined when youassign the material to an object (as described in Functional and Vector Material Proper-ties).

Mx=X

My=Y

Mz=Z

y

M

x

z






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Radial Vector Functions

A radial vector lying within a single plane is defined to always point radially outward from acenter point. Radial vectors are defined in the general form:

where for a vector lying in the yz-plane:

You specify the magnitude and center point that are used to define the radial vector. Itsorientation with the model’s coordinate system is defined when you assign the material toan object (as described under Functional and Vector Material Properties.)

M Mxi My j Mzk+ +=

Mx 0=

My My

y2

z2

+--------------------=

Mz Mz

y2

z2

+--------------------=



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Tangential Vector Functions

A tangential vector lying within a single plane is defined to point tangentially from a centerpoint. In effect, it is the tangent of a radial vector. Tangential vectors are defined in thegeneral form:

where for a vector lying in the xy-plane:

Its orientation is defined when you assign a material to an object.

M Mxi My j Mzk+ +=

Mx My–

x2

y2

+---------------------=

My Mx

x2

y2

+---------------------=

Mz 0=


Maxwell 3D — Boundary/Source ManagerTopics:

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Boundary/Source ManagerChoose Setup Boundaries/Sources to:

• Define boundary conditions that control how the electric or magnetic field behaves atobject faces, planes of symmetry and periodicity, and edges of the problem region.

• Define sources of voltage, charge, and current.• Identify conductors in which eddy currents are induced.

When you choose Setup Boundaries/Sources from the Executive Commands menu, the3D Boundary/Source Manager window appears, as shown below:

Boundary/Source ManagerModifying Boundary Condi-tions and Sources

Eddy Current BoundariesSelecting Objects and FacesTool Bar FunctionsBoundary/Source ManagerMenu Commands

Defining Boundaries andSources

Functional Boundaries andSources

Setting the Eddy Effect



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Modifying Boundary Conditions and SourcesIf you are modifying boundary conditions and sources after a solution has been gener-ated, the Maxwell 3D displays the following message:

WARNING

If you make changes to the boundary setupand save those changes, all solution datawill be deleted and will have to be recomputed.Pick “View Only” if no changes are to be saved,“Modify” if changes are to be saved, or “Cancel”to cancel this operation.

• To display the existing sources and boundary conditions without modifying them,choose View Only.

• To change sources and boundary conditions, choose Modify.• To return to the main menu, choose Cancel.

Eddy Current BoundariesIf you are solving an eddy current model, the Set/Unset Eddy Effect window appears bydefault, allowing you to define which objects have the eddy effect on them.

Be certain to set the eddy effect on the desired objects before defining the boundariesand sources for the model.

This function is identical to the Model/Set Eddy Effect command.

Boundary/Source ManagerModifying Boundary Con-ditions and Sources







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Selecting Objects and FacesBefore creating a boundary or source, you must specify its location. This is done using theBoundary/Source Manager’s selection commands, which are described below. You mustselect an object or surface before you can assign a boundary condition or source to it.

Selecting With the Mouse

When you access the Boundary/Source Manager, the mouse is automatically placed inselect mode. To select objects or surfaces, click the left mouse button on them. You canalso use the other Select commands on the right mouse button menu to select items inthe model. The selection commands in the right mouse button (RMB) menu are:

The way the mouse selects items depends on how you’ve defined its snap mode. Bydefault, Grid and Vertex snaps are turned on.

Next Behind

Use the Next Behind command to select the object or face that lies behind the currentlyselected object or face. This command chooses objects or faces depending on the graph-ical pick mode. Next Behind does nothing if no object has been previously selected or ifthe object you select has nothing behind it.

> To select the object that is hidden behind or within your currently selected object:1. Select the object that contains or conceals another object to highlight it.2. Click and hold the RMB to obtain the menu.3. Choose Next Behind from the RMB menu. A list of objects appears.4. Select the object you wish to highlight.

The object obscured by the original object is selected while the original object is dese-lected.

Next Behind Selects the object or face that lies behind the currently selected object.Select All Selects all objects in the project window.Deselect All Deselects all selected objects.By Box Selects the objects that lie within a box that you draw.


Eddy Current BoundariesSelecting Objects andFaces

Selecting With theMouse

Picking Objects, Faces, orBoundaries

Selecting Existing Bound-aries and Sources

Things to ConsiderTool Bar FunctionsBoundary/Source ManagerMenu Commands






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Select All

Use the Select All command to select all objects in the project window. Even if the graph-ical pick mode is set to Face or Boundary, Select All selects only the objects in themodel.

> To select all the objects in the model:1. Click and hold the RMB to obtain the menu.2. Choose Select All from the RMB menu.

All objects are selected and highlighted.

Deselect All

Use the Deselect All command to deselect the objects you have previously selected.

> To deselect all the objects:1. Click and hold the right mouse button (RMB) to obtain the menu.2. Choose Deselect All from the RMB menu.

All objects in the view window are deselected.

By Box

Use the By Box command to create a box that selects the objects that lie within it.

> To select the objects that lie within a box:1. Click and hold the right mouse button (RMB) to obtain the menu.2. Choose By Box from the RMB menu.3. Double-click on the base vertex of your box. A set of blank coordinates fields

appear.4. Enter the lengths of the sides of the box.5. Choose Enter to accept the values or choose Cancel to cancel the action.

The objects within the box are highlighted. The box vanishes after the objects areselected.

This command is identical to the Edit/Select/By Volume command.



Selecting With theMouse

Picking Objects, Faces, orBoundaries








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Picking Objects, Faces, or Boundaries

The Pick options control what you can select with the mouse. They let you switchbetween selecting objects, surfaces, and entire boundaries.

If you switch between these selection modes, the surfaces or objects that you’ve alreadyselected remain selected.

Selecting Existing Boundaries and Sources

To select a boundary or source that has already been defined, highlight its name in theboundary and source list in the lower left corner of the Boundary/Source Manager win-dow. Information about it, such as the type and value of the boundary or source, appearsthroughout the Boundary/Source Manager window.

In the Boundary/Source Manager window, the boundaries you select are listed in theorder in which you created them. In the case where overlapping boundaries are formed,the overlap area accepts the most recently created boundary as the true boundary condi-tion.

Object Selects closed 2D or 3D geometric objects.Face Selects surfaces of objects.Boundary Selects boundaries.

Note: When selecting and creating existing boundaries, remember that in thecases of overlapping boundaries, the boundary you select will be the mostrecently created one. Only the most recently created boundary will betreated as the true boundary. The only exception to this is the case of currentdensity terminals, which cannot overwritten even by other terminals, and canbe selected as normal.



Selecting With the MousePicking Objects, Faces,or Boundaries

Selecting ExistingBoundaries andSources







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Things to Consider

Be aware of the following when selecting objects and surfaces to be assigned boundaryconditions or sources.

Selecting the Edges of the Problem Region

To assign boundaries or sources to the edges of the problem region, you must select thesurfaces of the background object. The background object is automatically created bythe system and defines the size of the solution region. It is treated like any other object inthe model when assigning sources and boundaries. You can select individual faces, or theentire background region.

If you have excluded the background object from your model, do not assign boundaryconditions or sources to it.

Selecting Objects and Surfaces That Lie Inside Other Objects

To select objects and surfaces that lie inside other objects (such as an object that lieswithin an air box, a conductive shield, or the background object), do one of the following:

• Make the objects on the outside of the model invisible using the Edit/Visibilitycommands. This is useful when you want to select objects using the mouse. Since themouse cannot select invisible objects, you can select the interior surfaces or objectsby clicking on them.

• Use the Edit/Select/By Name or Edit/Select/By Volume commands to select objectsor surfaces inside the model.

• Use the Next Behind command on the right mouse button menu. This selects theobject that lies behind the one you initially selected. This command does nothing if noobjects have been previously selected.



Selecting With the MousePicking Objects, Faces, orBoundaries








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Tool Bar FunctionsThe tool bar, located just beneath the menu bar, provides icons that can be used to exe-cute certain commands. Click on the icon to activate its command. To see what the com-mand does without activating it, click on the icon and hold down the left mouse button.

Click on the image of the icon below to access the online documentation on the icon com-mand:

Boundary/Source Manager Menu CommandsThe following menus are available in the Boundary/Source Manager:

File Saves your work and exits the Boundary/Source Manager module.Edit Selects objects in your model and changes your boundary conditions;

Edits attributes and the visibility of the objects in your model; clearsboundaries and sources; restores cleared boundary conditions andsources.

View Changes the viewing settings. This is identical to the 3D Modeler menucommand.

Model Sets the functions, preferred units, and the eddy effect; shows conduc-tion paths.

Window Changes the settings of the view windows. This menu is identical to theone in the 3D Modeler.

Help Accesses the online documentation.


Eddy Current BoundariesSelecting Objects and FacesTool Bar FunctionsBoundary/Source Man-ager Menu Commands

Model CommandsModel/FunctionsModel/UnitsModel/Set Eddy EffectModel/Pick TerminalsModel/Show Conduc-tion Paths

Model/Verify Conduc-tion Paths






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Model Commands

The following commands are available in the Model menu:

Model/Functions

Choose Model/Functions to define mathematical functions that give the value of thepotential, current density, charge density, and so forth. The following window appears.

> To enter a new function:1. Choose Model/Functions. The Functions window appears.2. Enter the name of the new function in the field to the left of the equals sign.

Functions Defines mathematical functions.Units Defines the units you prefer on your variables.Set Eddy Effect Eddy Current. Turns on the eddy effect.Pick Terminals Creates terminals in the model.Show ConductionPaths

Computes and displays all the conduction paths in your model.

Verify ConductionPaths

Verifies the correctness of the conduction paths in your model.










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3. Enter the definition of the function in the field to the right of the equals sign.4. Choose Add.

The function now appears in the list and can be used to define functional boundaries andsources.

> To modify an existing function:1. Choose Model/Functions. The Functions window appears.2. Select the function you wish to modify. The function appears in the fields beside

the equals sign.3. Double-click on the values of the function you wish to change.4. Enter the new values for the function.5. Choose Update to add the function to the list.

The new function appears in the list.

> To delete a function:1. Choose Model/Functions. The Functions window appears.2. Select a function to highlight it.3. Choose Delete.

Model/Units

Choose Model/Units to specify the units of your boundaries and sources.

> To choose your preferred units:1. Choose Model/Units. A Select Units Preferences window appears.2. Select the quantities you wish to change.3. Select the new units from the list of units in the right of the screen.4. Choose OK to accept the new units or Cancel to ignore the changes.5. Repeat steps 2 through 4 for changing units in additional quantities.

The units change to your new settings.










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Model/Set Eddy Effect

Eddy Current

Choose this command to do the following:

• Specify the behavior of eddy currents and the AC magnetic field in conductors. Whenyou activate the Eddy effect setting, the solver computes the induced eddy currents.

• Specify the Displacement Current on the objects in the model.

Typically, background objects are excluded from eddy and displacement current settings.

> To select conductors in which eddy currents occur:1. Choose Model/Set Eddy Effect. The following window appears:

2. Select Eddy effect (the default) to begin assigning the eddy effect settings to theselected objects.

3. Select the conductor’s name from the list.4. To turn on the eddy effect in the selected conductors, choose Set.5. To turn off the eddy effect in the selected conductors, choose Unset.6. Optionally, choose Suggested Values to use the suggested default eddy effect

assignments. This setting typically forces all non-background objects included inthe model to be assigned the eddy effect.

7. Choose Done when you are finished.










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Setting Displacement Currents

You may also use the Set/Unset Eddy Effect window to define the displacement currenton the objects.

> To select the conductors for which displacement currents occur:1. Choose Model/Set Eddy Effect. The following window appears:

2. Select Displacement current.3. Select the conductors to which to assign a displacement current from the list.

Selected names become highlighted.4. To turn on the displacement current assignment in the selected conductors,

choose Set Disp.5. To turn off the displacement current assignment in the selected conductors,

choose Unset Disp.6. Optionally, choose Suggested Values to use the suggested default displacement

current assignments. This setting typically forces all non-background objectsincluded in the model to be assigned with displacement currents.

7. Choose Done when you are finished.










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Model/Pick Terminals

Use this command to calculate the current or voltage terminals on the selected objects inyour model. Terminals can be picked directly by selecting the appropriate face of a 3Dobject or by selecting 2D objects in the model. Terminals can be either planar faces or 2Dobjects.

> To create a terminal:1. Select an item to highlight it.2. Choose Model/Pick Terminals. The Pick Terminals window appears.3. Select Use only 2D objects to use only 2D objects as terminals. This box is

selected by default. Deselect the box to disable it.4. Select the Terminal Type you wish to compute. Branch terminal computes any

branching coil terminals in the model. Outer Terminal computes the terminals onthe edges of the region.

5. Choose OK to pick the terminals or choose Cancel to cancel the calculation.

A status bar appears during the conduction solution, showing its progress as it computesthe conduction paths for the terminals. You may interrupt the computation by choosingAbort.

The terminals for the objects are created and added to the boundary list.

Model/Show Conduction Paths

This command computes and displays the conduction paths in your model. Calculate con-duction paths is a memory-consuming process and should be used only when necessary,such as when a terminal is created or a current density source is specified.

> To proceed with the calculation:1. Select the name of the conduction path.2. Choose Done.

The calculation continues for all the conduction paths.










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Model/Verify Conduction Paths

Use this command to verify the correctness of the computed current conduction paths.

> To verify the conduction path:• Choose Model/Verify Conduction Paths.

The conduction paths in the model are corrected and verified.










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Defining Boundaries and Sources> In general, to define a boundary condition or source:

1. Select the Graphical Pick of the object, face, or boundary to which you will assigna value. For example, if you want to select the face of an object, choose Face. Inthis case, when you click in the view window, the mouse selects the faces ofobjects at the chosen position.

2. Select the face or object using the selection commands.3. Select whether you want to assign a Boundary or a Source.

• Select Boundary to specify the surface behavior of the electric or magnetic field.• Select Source to define a source of electric or magnetic field.

4. Select the type of boundary condition or source to be assigned to the selectedobject or surface.

5. Enter the name for the boundary or source type or accept the default.6. Select which boundaries are functional and which are constant.7. Select the units for the boundary or source.

8. Enter the Value of the boundary or source. When entering current, the arrowassociated with current in the selected object shows the direction as if a positivevalue is entered for the current. If a negative value is entered the actual currentflow direction is opposite to what the arrow shows. Choose Swap Direction toreverse the direction of the arrow.

9. Choose Assign to create the new boundary or source.

The new boundary or source is then added to the boundary and source listing in the lowerleft corner of the Boundary/Source Manager window.

Note: Instructions for defining specific boundary and source types are given in:• Electrostatic Boundary Conditions• Electrostatic Sources• Magnetostatic Boundary Conditions• Magnetostatic Sources• Eddy Current Boundary Conditions• Eddy Current SourcesMake sure that you include the required field sources and references for thesolver type you’ve selected.








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Functional Boundaries and SourcesIn the Boundary/Source Manager, functional boundaries and sources are used to do thefollowing:

• Define the value of a boundary or source quantity (such as the voltage, magnetic field,or current density) using a mathematical relationship — such as one relating its valueto that of another quantity.

• Define the value of the current density or charge density as a function of position.

• If parametric analysis capability was purchased, identify which boundary or sourcequantities are to be varied during a parametric sweep. These variables are always setto constant values in the parametric analysis.

Defining a Functional Boundary or Source> In general, to define a functional boundary or source:

1. Select an edge or surface and specify the boundary condition or source. Be certainto avoid overlapping boundaries. If two or more boundary conditions overlap on thesame object, face, or surface, only the most recently created one will be used asthe true boundary. Only current density terminals cannot be overwritten in thismanner, even if you define a new current density terminal as the new boundary.

2. Choose Model/Functions to define math functions that describe the boundary orsource’s behavior. You can also define which boundary or source quantities areconstant or functional.

3. After defining the function, enter its name as the value for the functional boundaryor source quantity.

4. Choose Assign to create the functional boundary condition or source.

Note: The following cannot be defined as functions of position:• Permeability• Anisotropic properties• Magnetostatic voltage or current• Eddy current voltage or current• Impedence• Master and slave boundaries




Functional Boundariesand Sources

Defining a FunctionalBoundary or Source

UnitsOptionsFunctions of Position




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Units

This command is used to specify the units for the boundaries and sources in the model.

> To specify the units:1. Choose Units. The Select Units Preferences window appears.2. Select the preferred units.3. Choose OK.

The new units are specified.

Options

Choose this command to define which values are constants and which are functions. Typ-ically, this button is inactive, and will direct you to using the Model/Functions commandto define the functional values. The software treats non-functional values as constants bydefault.










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Functions of Position

You can define boundary and source quantities that vary as a function of position. Theexample below shows how a functional current density can be used to specify a uniformcurrent density in a cylindrical object. This allows a wound coil to be modeled more accu-rately than when you specify the total current in the coil (which does not force current tobe uniformly distributed throughout the coil’s cross-section).

Use the Model/Functions command to create a function for each component of the cur-rent density, JX, JY, and JZ. In the coil shown above, the components of current would be:

Jx = -8000((y-5)/sqrt((x-9)*(x-9)+(y-5)*(y-5)))Jy = 8000((x-9)/sqrt((x-9)*(x-9)+(y-5)*(y-5)))Jz = 0

Here, you only need to define JX and JY as functional — JZ is equal to a constant value ofzero.

JX J– mag θsin J– magy 5–( )

x 9–( )2 y 5–( )2+

----------------------------------------------------= =

y

x

JY Jmag θcos Jmagx 9–( )

x 9–( )2 y 5–( )2+

----------------------------------------------------= =

JX

JY

θ

(x=9, y=5)

J

JZ 0=










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Setting the Eddy EffectIn some situations, it makes more sense to use perfect conductors to simulate inducedcurrents instead of setting the eddy effect in regular conductors. All currents in perfectconductors are surface currents, simulating the behavior of ordinary conductors that carryhigh-frequency signals. In an eddy current simulation, perfect conductors are generallyused to simplify the computation process. Use the chart below to determine if you shoulduse the eddy effect or perfect conductors to simulate induced currents.

Does the objectcarry source

current?

Yes No

Use a regularconductor. Turnon eddy effect.

Let current flowhomogeneously

through theconductor?

Use a regularconductor. Turnoff eddy effect.

Let currentflow only onconductor’s

surface?

Use a perfectconductor. Turnoff eddy effect.

Simulate exactinduced currentdistribution in

the conductor?

Let fields

Do not let fieldspenetrate;

assume surfacecurrent opposes

the fields?

Simulate exactsource currentdistribution inthe conductor?

penetrate butdo not compute

inducedcurrent?

Yes

Yes

Yes

Yes

Yes

Yes

No

No

No

No





Setting the Eddy EffectEddy Effect and AC Mag-netic Field Behavior



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Eddy Effect and AC Magnetic Field Behavior

The three types of AC magnetic field behavior that can be simulated using the EddyEffect command are shown below.

Object A shows the behavior of the H-field when an object is identified as a conductor withno eddy current effect. The magnetic field passes completely through the conductor andinduces no currents in it.

Object B shows the behavior of the H-field when eddy currents are induced in a conduc-tor. The magnetic field penetrates the conductors to the skin depth. The eddy current willbe concentrated near the surface, falling off rapidly past the skin depth.

Object C shows the behavior of the H-field when an object is identified as a perfect con-ductor. The magnetic field cannot penetrate into the conductor. All currents are modeledas surface currents — that is, currents with zero skin depth. This behavior occurs in con-ductors that carry high-frequency currents.

H-field

A — Regular Conductor, B — Regular Conductor, C - Perfect Conductor,

EddyCurrents

SkinDepth

SurfaceCurrents

Eddy Effect OFF Eddy Effect ON

Direction

Eddy Effect OFF





Setting the Eddy EffectEddy Effect and AC Mag-netic Field Behavior



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Required Field Sourcesand References

Electrostatic Sourcesand References

Magnetostatic Sourcesand References

Eddy Current Sources andReferences

Electrostatic Boundary Con-ditions

Electrostatic SourcesMagnetostatic BoundaryConditions

Magnetostatic SourcesEddy Current BoundaryConditions

Eddy Current Sources

Required Field Sources and ReferencesEach field solver requires you to specify sources of electric or magnetic fields, and refer-ences for computing these fields. Solver requirements are given under:

• Electrostatic Sources and References• Magnetostatics Sources and References• Eddy Current Sources and References

You must specify at least one of the boundary conditions or sources listed in these sec-tions, so the simulator will be able to compute accurate values for fields and parameters.

Electrostatic Sources and ReferencesRequired DC Electric Field Sources

Specify at least one of the following as a source of electric fields:

• The charge on a surface or object.• The charge density on a surface or inside an object.• The voltage difference between two surfaces. Define the electric potential on each

surface using either a voltage boundary or a voltage source.Required References for Electric Potential

Include at least one of the following as a reference for computing the electric potential:

• A voltage boundary.• A voltage source.• An odd symmetry (flux normal) boundary.



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Magnetostatic Sources and ReferencesRequired DC Magnetic Field Sources

Define at least one of the following as a source of static magnetic fields:

• The current in a conduction path.• The current density in a conductor.• The voltage differential across a conduction path.• The magnetic field on an outside surface.• A permanent magnet.

Reference for DC Magnetic Fields

If currents or current densities are the only sources of static magnetic fields in your model,set at least one outer boundary to the following:

• The default boundary conditions.• An odd symmetry (flux tangential) boundary.• An even symmetry (flux normal) boundary.

Eddy Current Sources and ReferencesRequired AC Magnetic Field Sources

Specify at least one of the following as a source of AC magnetic fields in your model:

• The current in a conduction path.• The current density in a conductor.• The magnetic field on an outside surface.

Reference for AC Magnetic Fields

If currents or current densities are the only sources of AC magnetic fields in your model,set at least one outer boundary to the following:

• The default boundary conditions.• An odd symmetry (flux tangential) boundary.• An even symmetry (flux normal) boundary.

Required Field Sources andReferences

Required Field Sourcesand References

Electrostatic Sources andReferences

Magnetostatic Sourcesand References

Eddy Current Sourcesand References






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Electrostatic Boundary ConditionsThe following boundary conditions are available for electrostatic problems:

Boundary Type E-Field Behavior Used to model…

Default Bound-ary Conditions(Natural andNeumann)

Field behaves as follows:• Natural boundaries — The normal

component of D changes by theamount of surface charge density. Nospecial conditions are imposed.

• Neumann boundaries — E is tangentialto the boundary. Flux cannot cross aNeumann boundary.

Ordinary E-field behavioron boundaries. Objectinterfaces are initially setto natural boundaries;outer boundaries are ini-tially set to Neumannboundaries.

Voltage Boundary is at a constant, known potential. Eis normal to the boundary.

Boundaries at knownpotentials.

Symmetry Field behaves as follows:• Even Symmetry (Flux Tangential) — E

is tangential to the boundary; its normalcomponents are zero.

• Odd Symmetry (Flux Normal) — E isnormal to the boundary; its tangentialcomponents are zero.

Planes of geometric andelectrical symmetry.

Matching(Master andSlave)

The E-field on the slave boundary is forced tomatch the magnitude and direction (or thenegative of the direction) of the E-field on themaster boundary.

Planes of symmetry inperiodic structures whereE is oblique to the bound-ary.


Electrostatic BoundaryConditions

Default Boundary Condi-tions

VoltageSymmetryMasterSlave






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Default Boundary Conditions

These boundary conditions are automatically defined for an electrostatic model:

• Natural boundaries are assigned to the surfaces between dielectrics.• Neumann boundaries are assigned to the outside edges of the problem region.

To leave a surface set to its default boundary condition, do nothing. Deleted boundaryconditions and sources automatically revert to the default boundary conditions.

Voltage

This condition sets the electric potential (voltage) on a surface to a specific value.

> To set a voltage boundary:1. Select the name of the boundary.2. With Boundary selected, select Voltage from the pull-down menu.3. Choose Units to specify the units for the values.4. Enter the electric potential on the boundary in the Value field.5. Choose Assign. The voltage is assigned to the boundary.

Symmetry

This boundary condition defines a plane of geometric or electric symmetry in a structure.Assign it only to the outer surfaces of the problem region.

> To set a symmetry boundary:1. Select the name of the boundary.2. With Boundary selected, select Symmetry from the pull-down menu.3. Select the type of symmetry:

4. Choose Assign. The boundary is applied to the model.

Even Symmetry (flux tangential) The signs of the voltages and charges are thesame on both sides of the symmetry plane.

Odd Symmetry (flux normal) The signs of the voltages and charges areopposite on either side of the symmetry plane.










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Master

Assigning a master boundary is the first step in creating matching boundaries that modelplanes of periodicity where the E-field on one surface matches the E-field on another. Thefield on the master boundary is mapped to the slave boundary. Assign master boundariesonly to the outer surfaces of the problem region.

> To set a master boundary:1. With Boundary selected, choose the name of the boundary.2. Select Master from the pull-down menu. The following fields appear:

3. Change the mouse mode to Position using the right mouse button menu.4. Select the origin of the master boundary, or enter its coordinates using the X, Y,

and Z fields. You must select a vertex point of an object.5. Choose Set Origin. The origin’s coordinates appear next to the button.6. Select the point defining the u-axis of the boundary as described in step 3.7. Choose Set Upoint. The point’s coordinates appear next to the button.8. Select the point defining the v-axis of the boundary as described in step 3.9. Choose Set Vpoint. The point’s coordinates appear next to the button.10.Choose Assign.










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Slave

Assigning a slave boundary is the second step in creating matching boundaries. The fieldon the master boundary is mapped to the slave boundary.

> To set a slave boundary:1. With Boundary selected, choose the name of the boundary.2. Select Slave from the pull-down menu. The following fields appear:

3. In the Master field, enter the name of a master boundary that the slave boundaryis assigned to. The most recently defined master boundary automatically appears.

4. Set the field behavior on the boundary. Under Relation, select:

5. Change the mouse mode to Position using the right mouse button menu.6. Set the Axis Definition for the origin, u-axis, and v-axis of the slave boundary as

you did for the master boundary.7. Choose Assign.

Es = Em The slave and master boundaries have same magnitude and direction.Es = – EmThe slave and master boundaries have same magnitude but opposite

direction.

Note: You must define a master boundary before creating the slave boundariesthat are associated with it. Assign slave boundaries only to the outer sur-faces of the problem region.










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Electrostatic SourcesThe following sources are available for electrostatic problems:

Floating Conductor

This type of source models conductors at unknown potentials and specifies the totalcharge on the conductor.

> To define a floating conductor:1. With Source selected, choose the name of the source.2. Select Floating Conductor from the pull-down menu.3. Choose Units to specify the units for the values.4. Enter the charge on the boundary in the Value field.5. Choose Assign.

Source Type of Excitation

Floating Conductor Used to model conductors at unknown potentials.

Voltage The DC voltage on a surface or object.

Charge The total charge on a surface or object (either a conduc-tor or dielectric).

Charge Density The charge density in an object.




Magnetostatic BoundaryConditions





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Voltage

This type of source sets the electric potential (voltage) on a surface to a specific value.

> To set a voltage source:1. With Source selected, choose the name of the source.2. Select Voltage from the pull-down menu.3. Choose Units to specify the units for the values.4. Enter the electric potential in the Value field.5. Choose Assign.

Voltage sources are identical to voltage boundaries.

Charge

This type of source defines the total charge on a surface or object. The potential on thecharge is computed during the solution.

> To define a charge source:1. With Source selected, choose the name of the source.2. Select Charge from the pull-down menu.3. Choose Units to specify the units.4. Enter the charge in the Value field.5. Choose Assign.

Charge Density

This type of source defines the charge density on a surface or object.

> To define the charge density on a surface or object:1. With Source selected, choose the name of the source.2. Select Charge Density from the pull-down menu.3. Choose Units to specify the units.4. Enter the charge density in the Value field.5. Choose Assign.









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Magnetostatic Boundary ConditionsThe magnetostatic field solver allows you to define the following types of boundaries:

Boundary Type H-Field Behavior Used to model…


Field behaves as follows:• Natural boundaries — H is continuous

across the boundary.• Neumann boundaries — H is

tangential to the boundary and fluxcannot cross it.

Ordinary field behavior.Initially, object interfacesare natural boundaries;outer boundaries andexcluded objects are Neu-mann boundaries.

Magnetic Field(H-Field)

The tangential components of H are set topre-defined values. Flux is perpendicular.

External magnetic fields.

Symmetry Field behaves as follows:• Odd Symmetry (Flux Tangential) — H

is tangential to the boundary; itsnormal components are zero.

• Even Symmetry (Flux Normal) — H isnormal to the boundary; its tangentialcomponents are zero.

Planes of geometric andmagnetic symmetry.

Insulating Same as Neumann, except that current can-not cross the boundary.

Thin, perfectly insulatingsheets between touchingconductors.


The H-field on the slave boundary is forced tomatch the magnitude and direction (or thenegative of the direction) of the H-field on themaster boundary.

Planes of symmetry inperiodic structures whereH is oblique to the bound-ary.





H Field (Magnetic Field)InsulatingSymmetryMasterSlave





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These boundary conditions are automatically defined for a magnetostatic model:

• Natural boundaries are assigned to the surfaces between objects.• Neumann boundaries are assigned to the outside edges of the problem region.

To leave a surface set to its default boundary condition, do nothing. Deleted boundaryconditions and sources automatically reset to the default boundary conditions.

H Field (Magnetic Field)

This type of boundary defines external magnetic fields in a model. Assign it only to theouter surfaces of the problem region.

> To define a magnetic field boundary:1. With Boundary selected, choose the name of the boundary.2. Select H Field from the pull-down menu.3. Choose Units to specify the units.4. Enter the x-, y-, and z-components of the external field in their respective fields.5. Choose Assign.

Warning: Be careful when using this type of boundary! There are two basic things towatch out for:• Do not violate Ampere’s law!• All magnetic field boundaries must be connected to each other.

Defining disconnected magnetic field and even symmetry boundariescan produce unexpected results, as there is no unique solution tosuch problems.










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Insulating

This boundary condition is used to model very thin sheets of perfectly insulating materialbetween touching conductors. Current cannot cross an insulating boundary.

> To set an insulating boundary:1. With Boundary selected, choose the name of the boundary.2. Select Insulating from the pull-down menu.3. Choose Assign.

Symmetry

This boundary condition defines a plane of geometric or magnetic symmetry in a struc-ture. Assign it only to the outer surfaces of the problem region.

> To set a symmetry boundary:1. With Boundary selected, choose the name of the boundary.2. Select Symmetry from the pull-down menu.3. Select the type of symmetry:

4. Choose Assign.

Even Symmetry (flux normal) Current flows in the same direction on bothsides of the symmetry plane.

Odd Symmetry (flux tangential) Current flows in opposite directions on eitherside of the symmetry plane.

Warning: When using even symmetry boundaries, there are two things to watch outfor:• Do not violate Ampere’s law!• All magnetic field boundaries must be connected to each other.

Defining disconnected magnetic field boundaries and even symmetryboundaries can produce unexpected results, as there is no uniquesolution to such problems.










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Master

Assigning a master boundary is the first step in creating matching boundaries that modelplanes of periodicity where the H-field on one surface matches the H-field on another. Thefield on the master boundary is mapped to the slave boundary. Assign master boundariesonly to the outer surfaces of the problem region.

> To set a master boundary:1. With Boundary selected, choose the name of the boundary.2. Choose Master from the pull-down menu. The following fields appear:

3. Change the mouse mode to Position using the right mouse button menu.4. Select the origin of the master boundary, or enter its coordinates in the X, Y, and Z

fields. You must select a vertex point of an object.5. Choose Set Origin. The origin’s coordinates appear next to the button.6. Select the point defining the u-axis of the boundary as described in step 3.7. Choose Set Upoint. The point’s coordinates appear next to the button.8. Select the point defining the v-axis of the boundary as described in step 3.9. Choose Set Vpoint. The point’s coordinates appear next to the button.10.Choose Assign.










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Slave


> To set a slave boundary:1. With Boundary selected, choose the name of the boundary.2. Select Slave from the pull-down menu.3. In the Master field, enter the name of a master boundary that the slave boundary

is assigned to. The most recently defined master boundary automatically appears.4. Set the field behavior on the boundary. Under Relation, select:

5. Change the mouse mode to Position using the right mouse button menu. This letsyou select the three points that define the plane of the slave boundary.

6. Select the origin of the slave boundary, or enter its coordinates in the X, Y, and Zfields. You must select a vertex point of an object.

7. Choose Set Origin. The origin’s coordinates appear next to the button.8. Select the point defining the u-axis of the boundary as described in step 6.9. Choose Set Upoint. The point’s coordinates appear next to the button.10.Select the point defining the v-axis of the boundary as described in step 6.11.Choose Set Vpoint. The point’s coordinates appear next to the button.12.Choose Assign.


Hs = Hm The slave and master boundary fields have same magnitudeand direction.

Hs = –Hm The slave boundary field has same magnitude but oppositedirection from the master boundary field.










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Magnetostatic SourcesThe following sources of magnetic fields are available for magnetostatic problems:

In addition, permanent magnets serve as sources of magnetic fields.

Voltage

This type of source sets the voltage on a surface to a specific value. Use it to set up a volt-age drop across a conduction path to cause current to flow.

> To set a voltage source:1. With Source selected, choose the name of the source.2. Select the outside surface of a conductor in the conduction path.3. Select Voltage from the pull-down menu.4. Choose Units to specify the units.5. Enter the voltage on the surface in the Value field.6. Choose Assign.


Voltage The DC voltage on a surface or object.

Voltage Drop The voltage drop across a sheet object.

Current The total current in a conductor.

Current Density The current density in a conductor.

Current Density Terminal The terminal source current.

Warning: For current to flow, you must define a minimum of two voltage sources or avoltage drop. Each source must be set to a different voltage. Current flowsfrom surfaces at higher voltages to surfaces at lower voltages.





Eddy Current BoundaryConditions




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Voltage Drop

This type of source sets the voltage drop across a sheet object to a specific value. Thevoltage drop applies only to sheet objects:

> To set a voltage drop:1. With Source selected, choose the name of the source.2. Select Voltage Drop from the pull-down menu.3. Select the sheet object to specify the voltage drop on.4. Choose Units to specify the units.5. Enter the voltage drop on the surface in the Value field.6. Choose Assign.

Current

Specifies the total current in a conduction path. The conduction path may be containedcompletely within the problem region (for example, a coil), or may touch the edges of theproblem region.

> To set a current source:1. With Source selected, choose the name of the source.2. Select the outside surface of a conductor in the conduction path.3. Select Current from the pull-down menu.4. Choose Units to specify the units.5. Enter the current on the surface in the Value field.6. Choose Solid or Stranded from the toggle box to define the current source as a

solid or stranded conductor.7. Choose Assign.









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Current Density

This command specifies the x-, y-, and z-components of the current density in a conduc-tion path. If the current density is a function of position, the value is entered in ampere/m2,even if you change the units in the problem.

> To define the current density:1. With Source selected, choose the name of the source.2. Select the conductor in which you would like to specify the current density.3. Select Current Density from the pull-down menu. The following fields appear:

4. Choose Units to specify the units.5. Enter the x-, y-, and z-components of the current density in their respective fields6. Choose OK to accept the objects or choose Cancel to cancel the action.

Current Density Terminal

This option specifies which object is the current density terminal in the model.

> To define the current density terminal:1. Select the 2D object or face to which to assign the terminal.2. Select Source, then choose Current Density Terminal from the source list.3. Choose Assign.

The object is now defined as a current density terminal.




Magnetostatic SourcesVoltageVoltage DropCurrentCurrent DensityCurrent Density Termi-nal





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Eddy Current Boundary ConditionsThe eddy current field solver allows you to define the following types of boundaries:

Boundary Type H-Field Behavior Used to model…


Field behaves as follows:• Natural boundaries — H is continuous

across the boundary.• Neumann boundaries — H is

tangential to the boundary and fluxcannot cross it.

Ordinary field behavior.Initially, object interfacesare natural boundaries;outer boundaries andexcluded objects are Neu-mann boundaries.

Magnetic Field The tangential components of H are set topre-defined values. Flux is perpendicular.

External AC magneticfields.

Symmetry Field behaves as follows:• Odd Symmetry (Flux Tangential) — H

is tangential to the boundary; itsnormal components are zero.

• Even Symmetry (Flux Normal) — H isnormal to the boundary; its tangentialcomponents are zero.

Planes of geometric andmagnetic symmetry.

Impedance Includes the effect of induced currentsbeyond the boundary surface.

Conductors with verysmall skin depths.

Insulating Same as Neumann, except that current can-not cross the boundary.

Perfectly insulating sheetsbetween conductors.

Radiation No restrictions on the field behavior. Unbounded eddy currents.


The H-field on the slave boundary is forced tomatch the magnitude and direction (or thenegative of the direction) of the H-field on themaster boundary.

Planes of symmetry inperiodic structures whereH is oblique to the bound-ary.






H Field (Magnetic Field)SymmetryMasterSlaveInsulatingRadiationImpedance




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These boundary conditions are automatically defined for an eddy current model:


To leave a surface set to its default boundary condition, do nothing. Deleted boundaryconditions and sources automatically reset to the default boundary conditions.


This type of boundary defines external magnetic fields in a model. Assign it only to theouter surfaces of the problem region. Regardless of the model’s drawing units, magneticfield values are entered in teslas.

> To define a magnetic field boundary:1. With Boundary selected, choose the name of the boundary.2. Select H Field from the pull-down menu.3. Choose Units to specify the units.4. Enter the x-, y-, and z-components of the external field in their respective fields.5. Enter the phase angle, θ, of the external field in the Phase field.6. Choose Assign.

Warning: Be careful when using this type of boundary! There are two basic things towatch out for:• Do not violate Ampere’s law!• All magnetic field boundaries must be connected to each other.











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Symmetry

This boundary condition defines a plane of geometric or magnetic symmetry in a struc-ture. Assign it only to the outer surfaces of the problem region.

> To set a symmetry boundary:1. With Boundary selected, choose the name of the boundary.2. Select Symmetry from the pull-down menu.3. Select the type of symmetry:

4. Choose Assign.

Even Symmetry (flux normal) Currents flow in the same direction on bothsides of the symmetry plane, and are in phase.

Odd Symmetry (flux tangential) Currents flow in opposite directions on eitherside of the symmetry plane, 180° out of phase.

Warning: Be careful when using even symmetry boundaries! There are two basicthings to watch out for:• Do not violate Ampere’s law.• All magnetic field boundaries must be connected to each other.











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Master

Assigning a master boundary is the first step in creating matching boundaries that modelplanes of periodicity where the H-field on one surface matches the H-field on another. Thefield on the master boundary is mapped to the slave boundary. Assign master boundariesonly to the outer surfaces of the problem region.

> To set a master boundary:1. With Boundary selected, choose the name of the boundary.2. Select Master. The following fields appear:

3. Change the mouse mode to Position using the right mouse button menu.4. Select the master boundary, or enter its coordinates using the X, Y and Z fields.

You must select a vertex point of an object.5. Choose Set Origin. The origin’s coordinates appear next to the button.6. Select the point defining the u-axis of the boundary as described in step 3.7. Choose Set Upoint. The point’s coordinates appear next to the button.8. Select the point defining the v-axis of the boundary as described in step 3.9. Choose Set Vpoint. The point’s coordinates appear next to the button.10.Choose Assign.










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Slave


> To set a slave boundary:1. With Boundary selected, choose the name of the boundary.2. Select Slave from the pull-down menu.3. In the Master field, enter the name of a master boundary that the slave boundary

is assigned to. The most recently defined master boundary automatically appears.4. Set the field behavior on the boundary. Under Relation, select:

5. Change the mouse mode to Position using the right mouse button menu. This letsyou select the three points that define the plane of the slave boundary.

6. Set the Axis Definition for the origin, u-axis, and v-axis of the slave boundary thesame way you did for the master boundary.

7. Choose Assign.

Insulating

This boundary condition is generally used to model very thin sheets of perfectly insulatingmaterial between touching conductors. Current cannot cross an insulating boundary.

> To set an insulating boundary:1. With Boundary selected, choose the name of the boundary.2. Choose Insulating from the pull-down menu and choose Assign.


Hs = Hm The slave and master boundary fields have the same magnitude anddirection. The fields on the boundaries are in phase.

Hs = – Hm The slave boundary field has the same magnitude but opposite direc-tion of the master boundary field. These boundaries are out of phase.










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Radiation

To simulate problems that allow fields to radiate infinitely far into space, you can definesurfaces to be radiation boundaries. The system absorbs the field at the radiation bound-ary, essentially ballooning the boundary infinitely far away from the structure.

> To assign a radiation boundary:1. Select the object to which to assign the radiation boundary.2. With Boundary selected, select Radiation from the pull-down menu.3. Choose Assign. The boundary is assigned to the object.

Impedance

This boundary condition is used to simulate the effect of induced currents in a conductorwithout explicitly computing them. Since the conductor itself is not included in the model(saving time needed to mesh and solve for currents), assign the impedance boundarycondition to an outside edge of the problem region or to an excluded object.

> To define an impedance boundary:1. With Boundary selected, choose the name of the boundary.2. Select Impedance from the pull-down menu.3. Enter the conductivity (in inverse ohm-meters) in the Conductivity field.4. Enter the conductor’s relative permeability in the Rel. Permeability field.5. Choose Assign.










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Eddy Current SourcesThe eddy current solver allows you to define the following sources of AC magnetic fields:

Current

Specifies the total AC current in a conduction path. The conduction path may be con-tained completely within the problem region (for example, a coil), or may touch the edgesof the problem region.

> To specify the total AC current:1. With Source selected, choose the name of the source.2. Select Current from the pull-down menu.3. Choose Units to specify the units.4. Enter the current in the Value field.5. Enter the phase (in degrees) in the Phase field.6. Choose Solid or Stranded from the toggle box to define the current source as a

solid or stranded conductor.

Current Density Terminal

Specifies the current density terminals in a conduction path. Terminals can only beassigned to 2D objects that completely cut through an object and whose edges match thesurface of their cutplane precisely, such as the top and bottom surfaces of cylinders.

> To define a current density terminal:1. Select the 2D object to define as the terminal.2. With Source selected, select Current Density Terminal from the pull-down menu.3. Choose Assign. The current density terminal is now defined in the model.


Current The total current in a conductor.

Current Density Terminal The current density terminals in a conductor.

Current Density The current density in a conductor.





Eddy Current SourcesCurrentCurrent Density Termi-nal

Current Density



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Current Density

Specifies the x-, y-, and z-components of the AC current density in a conduction path.

> To define the current density:1. With Source selected, choose the name of the source.2. Select the conductor in which you’d like to specify the current density.3. Select Current Density. The following fields appear:

4. Choose Units to specify the units.5. Enter the x-, y-, and z-components of the current density in their respective fields.6. Enter the phase angle, θ, of the current density in the Phase field.7. Choose Assign. The Select Terminal window appears.8. Select the names of the sheet objects to serve as the current density terminals.

This object must form an exact cross-section of the current density conductionpath.You must create 2D objects which represent locations where current flowsinto and out of the problem region, or branches at any location in the conductionpath. In current loops, any exact 2D cross-section may serve as a terminal.

9. Choose OK to accept the object or choose Cancel to cancel the action.





Eddy Current SourcesCurrentCurrent Density TerminalCurrent Density


Magnetostatic Boundary Conditions and SourcesTopics:

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Magnetostatic BoundaryConditions and Sources



SymmetryH Field (Magnetic Field)MatchingInsulating

Magnetostatic SourcesVoltageVoltage DropCurrentCurrent DensityCurrent Density Terminals

Magnetostatic Boundary Conditions and SourcesMaxwell 3D recognizes the following:

• Magnetostatic boundary conditions which describe the behavior of H on a surface.• Magnetostatic sources which specify the DC current or current density in a conductor.

Use them to specify the behavior of the magnetic fields in your model.

Magnetostatic Boundary ConditionsThe magnetostatic field solver allows you to define the following types of boundaries:

• Default (Natural and Neumann)• H Field (Magnetic Field)• Odd Symmetry (Flux Tangential)• Even Symmetry (Flux Normal)• Insulating• Matching (Master and Slave)


These boundary conditions are automatically defined for a magnetostatic model:


If a surface is not assigned any boundary conditions, it receives the default boundary con-dition. If you delete a boundary condition or source, the object resets to the default bound-ary condition or source values.



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Natural

Initially, all surfaces between two objects are defined as natural boundaries. At a naturalboundary,

• The tangential component of the H-field is continuous:

where:• HT1 is the tangential component of H in a defined region 1.• HT2 is the tangential component of H in a defined region 2.• Js is the surface current density.

• The normal component of B at the surface is continuous.

In most cases, there is no reason to modify the natural boundary condition at the surfacebetween two objects.

Neumann

If an outer surface — one on the edge of the problem region — is set to be a Neumannboundary, the magnetic field is tangential to that surface. The condition that holds is:

where Hn is the component of the H-field that is normal to the boundary.

A Neumann boundary models a sort of magnetic wall that prevents any flux from crossingthe boundary. If a boundary is sufficiently far away from any current sources and the mag-nitude of the H-field at the boundary is small, a Neumann boundary has a relatively smallimpact on the overall field pattern.

All surfaces bordering an object you have defined as non-existent are initially set to beNeumann. A Neumann boundary is also the default condition for surfaces on the edge ofthe problem region — that is, surfaces exposed to non-meshed space.

HT 1 HT 2 JS+=

Hn 0=








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Symmetry

A symmetry boundary models a plane of symmetry in a structure. Use this type of bound-ary condition to take advantage of geometric and magnetic symmetry in a structure.Doing so enables you to reduce the size of your model, which helps to conserve comput-ing resources. Two types of symmetry are available:

• Odd Symmetry (Flux Tangential)• Even Symmetry (Flux Normal)

These boundaries can only be assigned to the outside edges of the solution region.

Odd Symmetry (Flux Tangential)

Use an odd symmetry boundary to model a plane of symmetry in which current on oneside of a plane flows in the opposite direction to current on the other side of the plane.Magnetic flux is tangential to this type of boundary. To define an odd symmetry boundary,the simulator sets the selected edge to a Neumann boundary.

Image Solution Region

Current inCurrent out

The B-field is tangential to an odd symmetry boundary.








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Even Symmetry (Flux Normal)

Use an even symmetry boundary to define a plane of symmetry where the direction ofcurrent flow is the same on both sides of the plane. Magnetic flux is normal to this type ofboundary. To define an even symmetry boundary, the simulator sets the selected edge toa magnetic field boundary with a field value of zero — acting as a magnetic mirror to themodel.

Warning: Be careful when using even symmetry boundaries! There are some basicthings to watch out for:• Do not violate Ampere’s law.• All even symmetry boundaries must be connected to each other, or to

magnetic field boundaries. Defining disconnected magnetic field andeven source boundaries can produce unexpected results, as there isno unique solution to such problems.

Current inCurrent in

The B-field is perpendicular to an even symmetry boundary.









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A magnetic field boundary (also known as a value or Dirichlet boundary) is any surface onwhich the tangential component of the H-field is set to a specific value. Use this type ofboundary to model external magnetic fields.

For example, suppose a structure is placed in a uniform magnetic field (in amperes/meter)of , as shown below:

To define the external field, use magnetic field boundaries on all outer surfaces. Specifythe full vector value of H on each boundary as a function of x, y, and z — that is, definefunctional boundaries with a value of H=0.08X+0.04Y+0.01Z. The system automati-cally calculates the component of the field that is tangential to each surface and uses it asthe boundary condition. The normal component of the field is left as an unknown, but if allboundaries have been set properly, the results will come out as desired.

Warning: Be careful when using magnetic field boundaries! There are two basic thingsto watch out for:• Do not violate Ampere’s law.• All magnetic field boundaries must be connected to each other.

Defining disconnected magnetic field and even source boundariescan produce unexpected results, as there is no unique solution tosuch problems.

H 0.08 x 0.04 y 0.01 z+ +=

Magnetic field boundarieswith H = 0.08x + 0.04y + 0.01z

External magnetic field








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Violating Ampere’s Law

Ampere’s law dictates that:

where the closed line integral is any arbitrary path and the surface integral is the surfaceenclosed by that path.

Consider the structure below — a current-carrying cable inside a box. If the box’s outersurfaces are set to even symmetry (flux normal) boundaries or magnetic field boundarieswith Ht = 0, the magnetic field is perpendicular to the surfaces. Therefore, H•dl is equal tozero at all points along a path that coincides with the edge of the box. The integralbecomes:

Since there is non-zero current enclosed by the line integral, this violates Ampere’s law.

In most cases, you can avoid violating Ampere’s law by leaving the outside surfaces of amodel set to the default boundary conditions or by using superposition of magnetic fields.

H dl•c∫° J ds•

s∫∫=

H dl•c∫° 0=

J > 0

Magnetic Field or

Ht=0Even Symmetry:

All outer surfaces —








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Superposition

If a problem does not contain nonlinear materials, superposition of magnetic fields can beused to avoid violating Ampere’s law.

For example, assume that you are modeling a device that is in an external magnetic fieldof 0.1 amperes/meter in the y direction. To do so, you might define the outer surfaces tobe magnetic field boundaries set to a vector value of 0.1 ampere/meter in the y direction.However, if there are currents cutting through the problem space, the pre-set boundaryconditions might collide with Ampere’s law. In such a case, you can use superposition.

> Superimpose the field solutions as follows:1. Solve the problem with the external field and no source currents.2. In the Post Processor, save the results to a file using the Data/Calculator/Write

command.3. Solve the problem with source currents but with no external field.4. Using the data calculator in the Post Processor, read the first solution back into

memory and add it to the second solution.

The result is the superposition of the two solutions.








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Disconnected Magnetic Field and Even Symmetry Boundaries

All surfaces that are defined as magnetic field or even symmetry (flux normal) boundariesmust be contiguous. If two groups of these boundaries are separated by another type ofboundary, there is no unique solution to the problem and the system produces unex-pected results.

A perfect solenoid is shown below. The magnetic field inside the solenoid has an x-com-ponent only. Outside the solenoid, its magnitude is zero.

Magnetic field boundaries are needed on the front and back to force the H-field to be nor-mal to these surfaces. Because the field is zero along the top, bottom, and sides, youmight expect that these boundaries could be either default or magnetic field boundaries.However, to avoid violating the “disconnected magnetic field boundary” rule, all outsidesurfaces must be defined as magnetic field boundaries.

z

y

x

H J








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Matching

Matching boundaries allow you to model planes of periodicity where the H-field on onesurface exactly matches the H-field on another. They force the magnetic field at eachpoint on one surface (the “slave” boundary) to match the magnetic field at each corre-sponding point on the other surface (the “master” boundary). They are very useful formodeling devices such as motors, in which the electric field repeats every 180°, 120°,90°, or less. Basically, they enable you to model the smallest possible periodic segment ofthe device — reducing the amount of computing resources needed during the solution.

To set up matching boundaries, you must create both a master boundary and a slaveboundary. Unlike symmetry boundaries, H does not have to be tangential or normal tothese boundaries. The only condition is that the fields on the two boundaries must havethe same magnitude and direction (or the same magnitude and opposite directions).

Master

The simulator computes the magnetic field on a master boundary using currents, perma-nent magnets, and magnetic fields as input. The field is then mapped to the slave bound-ary.

Slave

The magnetic field on the slave boundary is forced to match the field on the masterboundary. The magnitude of the magnetic field on both boundaries is the same. However,the fields on the two boundaries can either point in the same direction, or in oppositedirections.








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When to Use Matching Boundaries

Matching boundaries enable you to take advantage of periodicity in a structure. For exam-ple, below is a diagram of the cross-section of a simple brushless DC motor. The field insuch a motor repeats itself every 90 degrees; that is, the field pattern in one quarter of themotor matches the magnitude and direction (or the opposite of the direction) of the fieldpattern in the other three quarters. With matching boundaries, all you have to model isone quarter of the structure.

Note that a symmetry boundary cannot be used to simulate periodicity because the mag-netic field is not necessarily either perpendicular or tangential to periodic surfaces. Forexample, in the quarter model shown on the right, the magnetic field is exactly perpendic-ular to the bounding surfaces only when the gap separating the permanent magnets isperfectly horizontal or vertical. For all other positions of the rotor, matching boundaries arerequired.

N

+–

S

S

N

N

HM

HS–

+

+

–

–

+

–

–

Master

SlaveMatchingBoundaries:

HM = HS








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Insulating

An insulating boundary prevents current from flowing across a surface — for instance, theinterface between two touching conductors. It acts like a thin, perfectly insulating sheetseparating the objects on one side of the boundary from those on the other side. No cur-rent can cross an insulating boundary; otherwise, it behaves like the default boundaryconditions.

Use insulating boundaries to model very thin layers of insulating material between con-ductors. Modeling thin insulating sheets in a structure with insulating boundaries savesyou the time needed to draw and assign material properties to such objects. Because thesystem does not have to explicitly generate a mesh inside the insulating layer, using aninsulating boundary also speeds up the solution process.

Warning: Insulating boundaries do not work if you define currents using voltagesources. Instead, specify the current or current density in the model’s con-ductors.








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Magnetostatic SourcesThe magnetostatic solver allows you to define the following sources of magnetic fields:

• Voltage• Voltage Drop• Current• Current Density• Current Density Terminal

Voltage

This type of source specifies the DC voltage on a surface, enabling you to define currentsin a model by specifying the voltage drop across a conduction path. Use it if one of the fol-lowing applies:

• You cannot explicitly specify the current density or net current inside a conductor, butknow the voltage drop across it.

• A conduction path in your model contains more than one type of material.

For current to flow, you must specify a minimum of two voltage sources, each set to a dif-ferent voltage. There must be a path for current to flow between these surfaces — that is,they must be connected by one or more conductors. Current flows from surfaces at highervoltages to those at lower voltages.

Voltage Drop

A voltage drop source specifies the DC voltage drop across a terminal. Use this type ofsource when one of the following applies:

• You cannot explicitly specify the current density or net current inside a conductor.• A conduction path in your model contains more than one type of material in the closed

loop.

The voltage drop applies only to sheet objects inside a closed loop.

Warning: Do not assign voltage sources to a conduction path where you specified thetotal current or the current density. You cannot mix current sources. Thisover-specifies your model, causing an error.








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Current

This type of source specifies the total DC current in a conductor. Use it if one of the follow-ing applies:

• You cannot explicitly specify the current density inside an object but know the netcurrent flowing through it.

• The object has been defined as a perfect conductor. In these objects, current isdistributed over the surface and no fields penetrate the conductor. You cannot definethe current density in a perfect conductor, and therefore must specify its total current.

• The model’s conductors are irregularly shaped, making it difficult to define the currentdensity.

When specifying the current in an object, an arrow appears, indicating the direction of thecurrent. The current direction shown by the arrow in the modeling region is always thepositive current direction. You can change the direction of the arrow by choosing theSwap Direction command.

During the solution process, the magnetostatic field solver uses the total current to com-pute the current density in the conduction path. This then serves as input to the DC mag-netic field solution.

Warning: All current that flows into the model through an outer surface must leavethrough another outer surface (or surfaces) in the same conduction path.Make sure that the direction of current on each surface is such that the totalcurrent for the conduction path adds up to zero.








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Magnetostatic SourcesVoltageVoltage DropCurrentCurrent DensityCurrent Density Termi-nals

Current Density

This type of source specifies the current density in amp/m2 in the selected conductor.Current density is generally used to define a uniform current distribution in a conductionpath. Current is distributed throughout the conductor according to the values you specifyfor the x-, y-, and z-components of the current density.

Keep the following things in mind when assigning current densities:

• Be careful not to violate the law of zero divergence!• Define current densities as functions of position in circular objects like coils. This lets

you specify a uniform current density in the coil’s cross-section (which cannot be donewhen defining the total current in the coil) to create a current density terminal.

• When it solves for magnetic fields, the system performs a conduction current solutionbefore performing the full static magnetic field solution. The result of the conductionsolution — the current density J — serves as input to the magnetostatic solution.However, the system does not include objects for which current densities are explicitlyspecified in the conduction simulation. It simply uses the current density as direct inputto the magnetostatic solver.

Current Density Terminals

Current density terminals are exact 2D cross-sections of the inside of a conductor. Theseterminals eliminate unwanted high values in the solver and result in a faster convergencein the final solution. You can have multiple terminals in a conduction path.

Note: When you exit the boundary manager after assigning a current density termi-nal, the software performs an error check to make sure that you haveassigned at least one current density terminal to every conduction path thathas current density sources.

A check is also made to ensure that you do not mix current sources and cur-rent density sources on the same conduction path. You are not permitted tomix stranded and non-stranded currents on the same conduction path.



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Magnetostatic SourcesVoltageVoltage DropCurrentCurrent DensityCurrent Density Termi-nals

Zero Divergence

Be careful when explicitly specifying current densities (as opposed to specifying the cur-rent in a conductor). You must set up your problem so that it is consistent with reality —that is, currents entering a region must also exit that region.

For instance, the example on the left violates this principle. Each side of the coil is repre-sented by a different object, each of which has a current density of 100 ampere/meter2.The conflict with reality arises at the ends of each object. The current supposedly flowsstraight to the end of each side, suggesting that charges are collecting there. Mathemati-cally, this violates the law of zero divergence.

The correct way to set up this problem is shown on the right. In this example, the currentdoes make a complete loop but no build-up of charge is implied.

It is also possible to set up the problem so that the current enters and exits from an outerboundary. For example, to model a cable carrying current through the problem region,place the two ends of the cables in contact with the outer boundaries of the background.Then, specify a current density. The current enters one side of the problem region andexits on the other, and does not violate the law of zero divergence.

∇ J• dρdt------ 0= =

Incorrect — Non-zero divergence Correct — Zero divergence

J J


Electrostatic Boundary Conditions and SourcesTopics:

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Electrostatic BoundaryConditions and Sources



NaturalNeumann

VoltageSymmetryMatching


Electrostatic Boundary Conditions and SourcesMaxwell 3D recognizes the following:

• Electrostatic boundary conditions which describe the behavior of E on a surface andenable you to specify the surface’s electric potential.

• Electrostatic sources which specify the charge, charge density, or electric potential onobjects and selected surfaces.

Use them to define sources of electric fields in your model.

Electrostatic Boundary ConditionsThe electrostatic solver allows you to assign the following boundary conditions:

• Default (Natural and Neumann)• Even Symmetry (Flux Tangential)• Odd Symmetry (Flux Normal)• Voltage• Matching (Master and Slave)


These boundary conditions are automatically defined for an electrostatic model:

• Natural boundaries are assigned to the surfaces between dielectrics.• Neumann boundaries are assigned to the outside edges of the problem region.

If a surface is not assigned any boundary conditions, it receives the default boundary con-dition. If you delete a boundary condition or source, the object resets to the default bound-ary condition or source values.



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Natural

Initially, all surfaces between dielectrics are defined as natural boundaries, which means:

• The tangential components of the E-field are continuous across the surface.• The normal component of the D-field at the surface is discontinuous by the amount of

the surface charge density:

where:• Dn1 is the normal component of the D-field in a defined region 1.• Dn2 is the normal component of the D-field in a defined region 2.• ρs is the surface charge density.

In most cases, there is no reason to modify the natural boundary condition at the surfacebetween two dielectrics. About the only time you need to change the boundary conditionthat’s assigned to a dielectric interface is when you wish to model the interface as a thinconductor using a voltage boundary.

Neumann

Initially, Neumann boundaries are assigned to the outside edges of the problem region.For these boundaries, the condition that holds is:

which means that the normal component of the D-field is zero, or that the charge on theboundary is zero. Therefore, the electric field is tangential to Neumann surfaces.

Neumann boundaries are identical to even symmetry (flux tangential) boundaries.

Dn1 Dn2– ρs=

Dn 0=

Electrostatic Boundary Con-ditions and Sources



NaturalNeumann





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Voltage

Use a voltage boundary, sometimes called a value or Dirichlet boundary, to identify a sur-face on which the electric scalar potential is at a specific value. Contours of equal poten-tial are parallel to voltage boundaries — each surface is at a single potential. The E-fieldis perpendicular to a voltage boundary.

For a description of how to set voltage boundaries in electrostatic problems, consult theSetup Boundaries/Sources section on voltage boundaries.

Surface Potential and Field Solutions

The potential on the surface of a conductor is all that Maxwell 3D needs to know aboutthat conductor. Because the region inside the conductor is at an equal potential, no elec-tric field exists there. Therefore, the electrostatic field simulator does not need to solve forthe potential inside the conductor. Whatever you specify as the potential on the surface isassumed to be the potential throughout the entire conductor.

Modeling Thin Conductors

Voltage boundaries can be used to model very thin conductors (that is, conductors with athickness at least two orders of magnitude smaller than their other dimensions). Forexample, to model two very thin metal plates with a dielectric sandwiched between them,define the top and bottom surfaces of the dielectric to be voltage boundaries. This simu-lates the presence of the plates without having to draw them. To model irregularly shapedthin conductors (such as striplines on a dielectric), draw the conductors using 2D objectsand then define the objects as voltage boundaries. Modeling thin conductors with voltageboundaries reduces the amount of computing resources used during the solution, sinceMaxwell 3D does not need to generate a mesh inside the conductors.

Warning: You must assign a voltage boundary to all non-floating conductors. Other-wise, the system treats those surfaces as natural boundaries which maycause the solver to generate an incorrect solution.




VoltageSurface Potential andField Solutions

Modeling Thin Con-ductors

SymmetryMatching




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Symmetry

A symmetry boundary models a plane of symmetry in a structure. Use this type of bound-ary condition to take advantage of both geometric symmetry and electric symmetry. Doingso enables you to reduce the size of your model — allowing you to conserve computingresources. Two types of symmetry boundaries are available:

• Even Symmetry (Flux Tangential)• Odd Symmetry (Flux Normal)


Even Symmetry (Flux Tangential)

Use an even symmetry boundary to define a plane of symmetry where the signs (positiveor negative) of the voltages and charges on one side of the plane are the same as thoseon the other side. Electric flux is tangential to the boundary and thus does not cross it. Todefine an even symmetry boundary, the simulator sets the selected edge to a Neumannboundary — acting as an electrical mirror to the model.

Image

The E-field is tangential to an even symmetry boundary.

+

+

+ ++

++++

+

PositiveCharge

PositiveCharge +

Solution Region

+

+

+++

++ + +

+




VoltageSymmetry

Even Symmetry (FluxTangential)

Odd Symmetry (FluxNormal)

MatchingElectrostatic Sources

Floating ConductorVoltageChargeCharge Density



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Odd Symmetry (Flux Normal)

Use an odd symmetry boundary to define a plane of symmetry where the signs (positiveor negative) of all charges and voltages on one side of the plane are the opposite of thoseon the other side. Electric flux is normal to the boundary. To define an odd symmetryboundary, the simulator sets the selected edge to a voltage boundary with a potential ofzero volts.


+

+

++

+

++ +

+

PositiveCharge

NegativeCharge

–

––

––

–

–

– –

The E-field is perpendicular to an odd symmetry boundary.




VoltageSymmetry

Even Symmetry (FluxTangential)

Odd Symmetry (FluxNormal)

MatchingElectrostatic Sources

Floating ConductorVoltageChargeCharge Density



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Matching

Matching boundaries allow you to model planes of periodicity where the E-field on onesurface matches the E-field on another. They are very useful for modeling devices suchas motors, in which the electric field repeats every 180°, 120°, 90°, or less. They enableyou to model the smallest possible periodic segment of the device — reducing the amountof computing resources needed during the solution.

To set up matching boundaries, you must create a master boundary and a slave bound-ary. Unlike symmetry boundaries, E does not have to be tangential or normal to theseboundaries. The only condition is that the fields on the two boundaries must have thesame magnitude and direction (or the same magnitude and opposite directions).

Master

The simulator computes the electric field on a master boundary using the charges andvoltages that you specified for the model as input. No other special conditions areimposed.

Slave

The electric field on the slave boundary is forced to match the field on the master bound-ary. The magnitude of the electric field on both boundaries is the same. The fields on thetwo boundaries can either point in the same direction, or in opposite directions.





MasterSlaveWhen to Use MatchingBoundaries




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When to Use Matching Boundaries

Consider a simple electrostatic micromotor in which the rotor is held at zero volts and thesix stator poles are switched between zero volts, 100 volts, and –100 volts. The E-fieldpattern at any point in time repeats itself every 180° — causing the field in one half of themotor to match the field in the other half.

If you use matching boundaries, you only need to model half of the motor, as shownbelow. The E-field on the slave boundary (the left side of the motor) is forced to match themagnitude and point in the opposite direction from the E-field on the master boundary(the right side of the motor) — simulating the field pattern that would occur if the entiremotor was modeled.

Note that a symmetry boundary cannot be used in place of matching boundaries in thisexample. The electric field is not necessarily either perpendicular or tangential to themotor’s periodic surfaces. In the example above, the electric field would be exactly tan-gential to the periodic surface only when the poles of the rotor are aligned with the polesof the stator. In the other positions of the rotor, the field is not tangential and matchingboundaries are required.

Slave Master

ESlave (us = 1, vs = –5)EMaster(um = 1, vm = 5)

0 volts

100 volts

-100 volts

vs vm

us, um





MasterSlaveWhen to Use MatchingBoundaries




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Electrostatic SourcesThe electrostatic solver allows you to define the following sources of electric field:

• Floating Conductor• Voltage• Charge• Charge Density

Floating Conductor

Floating conductor sources are used to model conductors at unknown potentials. Youspecify the total charge on the conductor. Its potential is computed by the system duringthe solution process, and is constant.

Charge on a floating conductor is assumed to be distributed on the surface of the conduc-tor in such a way as to cancel out the E-field inside the conductor. (If the E-field were notzero inside the conductor, charges would flow and the problem would not be static.)

Voltage

This type of source specifies the total DC voltage (electric potential) on a conductor. Notethat conductors that touch should be set to the same voltage or defined as a single volt-age source, since their potentials are identical.

Voltage sources are essentially the same as voltage boundaries.

Charge

This type of charge source defines the total charge on a surface or object. Its potential iscomputed during the field solution. If there is no net charge, accept the default of zero.

Charge on Conductors

On a conductor, the charge you specify is distributed over the surface as needed toensure that the E-field inside it is zero.

Charge on Dielectrics

If the object is not a conductor, charge is assumed to be uniformly distributed throughoutits volume.





Electrostatic SourcesFloating ConductorVoltageCharge

Charge on Conduc-tors

Charge on DielectricsCharge Density



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Charge Density

This type of source specifies the charge density in an object or on a surface. The object’sor surface’s potential is computed during the field solution. If there is no net charge,accept the default of zero.

Charge Density in Dielectrics

For charge density in dielectrics, constant values can be entered in any relevant units thatyou specify, but are typically entered in coulombs/meter3. For functional values of posi-tion, the charge density must be entered in MKS units. This is true for any functional val-ues that you specify.

• If you enter a constant charge density, charge is assumed to be uniformly distributedthroughout the dielectric in the density you specify.

• If you enter a functional charge density, charge is distributed throughout the volume ofthe dielectric according to the function of position that you specify.

The electric field inside the dielectric is not equal to zero.






Charge Density inDielectrics


Eddy Current Boundary Conditions and SourcesTopics:

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Eddy Current BoundaryConditions and Sources



NaturalNeumann


Odd Symmetry (FluxTangential)

Even Symmetry (FluxNormal)


When to Use Imped-ance Boundaries

RadiationEddy Current Sources


Eddy Current Boundary Conditions and SourcesMaxwell 3D recognizes the following:

• A set of eddy current boundary conditions which describe the behavior of H(t) on asurface.

• A set of eddy current sources which specify the AC current or current density inobjects and on selected surfaces.

Use them to define magnetic fields in your model.

Note: Remember that you must specify both a magnitude and a phase for all ACquantities.



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Eddy Current Boundary ConditionsThe eddy current field simulator allows you to define the following boundary conditions:

• Default (Natural and Neumann)• H Field (Magnetic Field)• Odd Symmetry (Flux Tangential)• Even Symmetry (Flux Normal)• Insulating• Matching (Master and Slave)• Impedance• Radiation


The Boundary/Source Manager automatically defines these boundary conditions for aneddy current model:


If a surface is not assigned any boundary conditions, it receives the default boundary con-ditions. If you delete a boundary condition or source, the object resets to the defaultboundary condition or source values.

Natural

Natural boundaries in eddy current problems behave the same way as natural boundariesin magnetostatic problems.

Neumann

Neumann boundaries in eddy current problems behave the same way as Neumannboundaries in magnetostatic problems. These boundaries have flux tangential symmetryin eddy current and magnetostatic problems.




NaturalNeumann










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Magnetic field boundaries (known as value or Dirichlet boundaries) are used to model thepresence of external AC magnetic fields. They behave the same way as magnetostaticmagnetic field boundaries. The only difference is that you must specify the magnitude andphase of the tangential components of H at the boundary (that is, the phase differencebetween the field at the boundary and the reference phase for the problem).

Symmetry

A symmetry boundary models a plane of symmetry in a structure. Use this type of bound-ary condition to take advantage of geometric symmetry and magnetic symmetry in astructure. Doing so enables you to reduce the size of your model, which helps to conservecomputing resources. Two types of symmetry are available:

• Odd Symmetry (Flux Tangential)• Even Symmetry (Flux Normal)


Odd Symmetry (Flux Tangential)

Use an odd symmetry boundary to model a plane of symmetry in which current on oneside of a plane flows in the opposite direction of current on the other side of the plane.This type of boundary behaves the same way as magnetostatic odd symmetry (flux tan-gential) boundaries. Currents on either side of the boundary are assumed to be 180° outof phase.

Warning: When using magnetic field boundaries, there are two things to watch out for:• Do not violate Ampere’s law.• All magnetic field boundaries must be connected to each other, or to

even symmetry (flux normal) boundaries. Defining disconnectedmagnetic field and even source boundaries can produce unexpectedresults, as there is no unique solution to such problems.




NaturalNeumann










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Even Symmetry (Flux Normal)

Use an even symmetry boundary to define a plane of symmetry when the direction of cur-rent flow is the same on both sides of the plane. This type of boundary behaves the sameway as magnetostatic even symmetry (flux normal) boundaries. Currents on both sides ofthe boundary are assumed to have the same phase.

Insulating

Insulating boundaries prevent current from flowing across a surface. They model thin, per-fectly insulating sheets that separate objects on opposite sides of a boundary.

Insulating boundaries in eddy current problems behave the same way as magnetostaticinsulating boundaries.

Matching

Matching boundaries model planes of periodicity where the H-field on one surface exactlymatches the H-field on another. They force the magnetic field at each point on one sur-face (the “slave” boundary) to match the magnetic field at each corresponding point onthe other surface (the “master” boundary).

Matching boundaries in eddy current problems behave the same way as magnetostaticmatching boundaries. The magnitude, direction, and phase of the magnetic field on themaster boundary is imposed on the slave boundary. Forcing the field on the slave bound-ary to point in the opposite direction from the field on the master boundary causes it tooscillate 180 degrees out of phase.

Warning: Be careful when using even symmetry boundaries! There are two basicthings to watch out for:• Do not violate Ampere’s law!• All even symmetry boundaries must be connected to each other, or to

magnetic field boundaries. Defining disconnected magnetic field andeven source boundaries can produce unexpected results, as there isno unique solution to such problems.




NaturalNeumann










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Impedance

Impedance boundaries allow you to simulate the effect of induced currents in a conductorwithout explicitly computing them. Use this boundary condition for models where:

• The skin depth in the conductor is less than two orders of magnitude smaller than thedimensions of the structure. In models like this, the meshmaker may not be able tocreate a fine enough mesh in the conductor to compute eddy currents.

• The magnetic field decays much more rapidly inside the conductor in the directionthat’s normal to the surface than it does in directions that are tangential to the surface.

• The AC current source is relatively far away from the surface where eddy currentsoccur, compared to the size of the skin depth.

The conductor itself is not included in the solution region. Instead, when setting up themodel, do one of the following:

• When drawing the model, make the surface along which eddy currents are to becomputed an outer surface of the problem region.

• Exclude the object from the problem region by making it part of the background object,or by making the object a perfect conductor in the Materials Manager. The solver doesnot find solutions inside a perfect conductor.

Then, when defining boundaries, assign an impedance boundary to this surface. Byentering the conductivity, σ, and the relative permeability, µr, of the object, you specify theskin depth of induced eddy currents. The simulator uses this skin depth value when com-puting the electromagnetic field solution. It assumes that the H-field falls off exponentiallyinside the conductor. The ohmic loss due to induced currents can then be computed fromthe tangential components of the H-field along the impedance boundary — the surface ofthe object that you are interested in.

Note: An impedance boundary only approximates the effect of eddy currents act-ing at a shallow skin depth. It does not directly compute them. In general, thefields modeled using an impedance boundary will closely match the field pat-terns that would actually occur in the structure. However, at discontinuities inthe surface (such as corners), the field patterns may be different.




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When to Use Impedance Boundaries

A typical situation where impedance boundaries can be used to reduce the complexity ofa model is shown below. Suppose you want to compute eddy current losses in the con-ductor next to the current source shown below on the left. If the source carries AC currentat a frequency of 1 MHz, the skin depth in the conductor is 6.6 x 10–5 meters. This is sev-eral orders of magnitude smaller than the conductor’s thickness. Since the conductorwhere currents are induced is also relatively far away from the current source, an imped-ance boundary can be used to model the induced currents — as shown on the right.

The conductor itself is not included in the model. Instead, the outside boundary of themodel is moved to the inside surface of the conductor. This outside surface is defined asan impedance boundary, using the conductivity and permeability specified previously.Since the simulator does not have to actually compute a solution inside the conductor, thefield solution is computed more quickly and uses less memory. After solving, you cancompute the ohmic loss for the surface using the solution calculator and plot the loss den-sity on the boundary.

Current Source1 MHz

0.5 m

Skin Depth = 6.6x10–5 m

Conductor:µr =1

σ = 5.8x107 S/m

0.5 m

ImpedanceBoundary:

µr =1σ = 5.8x107 S/m

Current Source1 MHz

Model without Impedance Boundary Model with Impedance Boundary

Outsideedge ofproblemregion

Thickness1x10-3 m




NaturalNeumann










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Radiation

Eddy Current only.

To simulate problems that allow electromagnetic fields to propagate infinitely far intospace, you can define surfaces to be radiation boundaries. Such a boundary conditionabsorbs the field so that no reflection of the waves back into the space of the solutionoccurs at the boundary.

In a far field region, field components are expressed by:

where:

and Z is the component of the E-field that is tangential to the surface.

Using the field impedance, the equation becomes:

which is used as a radiation boundary. The radiation boundary condition should be placedfar enough from the source of radiation so that the approximation of the far field in theregion of the boundary holds.

The second-order radiation boundary condition is an approximation of free space. Theaccuracy of the approximation depends on the distance between the boundary and theobject from which the radiation emanates.

A radiation surface does not have to be spherical. However, it should be exposed to thebackground, convex with regard to the radiation source, and located at least one-quarterof a wavelength away from the radiating sources. In some cases you may want to usesmaller distances.

E Zn H×–=

Zµε---=

n E× Zn– n H×( )×=




NaturalNeumann










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Eddy Current SourcesThe eddy current solver allows you to define the following sources of AC magnetic fields:

• Current• Current Density• Current Density Terminals

Current

This type of source specifies the AC current in a conductor. Use it if one of the followingapplies:

• You cannot explicitly specify the current density inside an object but know the netcurrent flowing through it.

• The object has been defined to be a perfect conductor. In these objects, current isdistributed over the surface and no fields penetrate the conductor. You cannot definethe current density in a perfect conductor, and therefore must specify its total current.

• The model’s conductors are irregularly shaped, making it difficult to define currentdensities as functions of position.

When specifying the current in an object, an arrow appears, indicating the direction of thecurrent. The current direction shown in the modeling region is always the positive currentdirection.

Current sources must be assigned constant values.

During the solution process, the total current serves as input to the AC magnetic fieldsolution. Eddy currents are computed if you set the eddy effect in the conductors that

Note: When defining AC current sources, you must specify both a magnitude andphase (that is, the phase difference between the current source and the ref-erence phase for the problem).

Eddy Current Boundary Con-ditions and Sources

Eddy Current Boundary Con-ditions


NaturalNeumann










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make up the conduction path.

Warning: All current that flows into the model through an outer surface must leavethrough another outer surface (or surfaces) in the same conduction path.Make sure that the direction of current on each surface is such that the totalcurrent for the conduction path adds up to zero.

Also, you must observe the following rules of applying eddy current sources:• No object may have more than two terminals per conduction

path.• You cannot mix outer terminals and branch terminals in an

object.• You cannot mix voltage, current, and current density sources on

an object.• All terminals must be planar faces or 2D sheet objects.• For coil terminals, you need to create a 2D sheet object that

matches the exact cross-section of your object in order to apply asource to it.




NaturalNeumann










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NaturalNeumann







CurrentCurrent DensityCurrent Density Termi-nals

Current Density

This type of source specifies the current density in amp/m2 in the selected conductor.Current density is generally used to define a uniform current distribution in a straightobject or a circular coil. Current is distributed throughout the object according to the val-ues you specify for the x-, y-, and z-components of the current density.

There are two things that you must keep in mind when assigning current densities in eddycurrent models:

• Be careful not to violate the law of zero divergence.• Define current densities as functions of position in circular objects like coils where you

want to maintain a uniform current density.

Current Density Terminals

Current density terminals are exact 2D cross-sections of the inside of a conductor whichact as current sources. These terminals eliminate unwanted high values in the solver andresult in a faster convergence in the final solution. Multiple terminals can exist in any con-duction path.

Note: When you exit the boundary manager, the software performs an error checkto make sure that you have assigned at least one current density terminal toevery conduction path that has current density sources.

A check is also made to ensure that you do not mix current sources and cur-rent density sources on the same conduction path. You are not permitted tomix stranded and non-stranded currents on the same conduction path.


Maxwell 3D — Executive ParametersTopics:

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Executive ParametersChoose Setup Executive Parameters to request that one or more of the following quan-tities be computed during the solution:

• A capacitance, inductance, or impedance matrix.• The virtual or Lorentz force on an object or group of objects.• The virtual or Lorentz torque on an object or group of objects.• If you have purchased the parametric analysis module, the matrix entries of a

parametric sweep.

When you select this command, a menu of all available executive parameters appears.The menu shown here lists all parameters; however, different parameters are availabledepending on which solver you selected. Choose the parameter to be computed andenter the appropriate information in the window that appears. A check box appears next toall parameters that have already been selected.

Executive ParametersExecutive Parameters Com-mands

Executive Parameters MenuCommands

Exiting an Executive Param-eters Command

Tool BarMatrix

The Return Path for Cur-rent

ForceTorque



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Executive Parameters CommandsThe Setup Executive Parameters commands allow you to select one or more of the fol-lowing quantities to be computed during the solution process:

Depending on the solver you have selected, different executive parameters are available.Click on the parameter for an explanation of it.

Executive Parameters Menu CommandsEach executive parameter setup window has the following menu commands:

Matrix A capacitance, inductance, or impedance matrix. Thespecific matrix that is computed depends on the solver.

Force The net force on an object or group of objects. Virtualforce is available for all solvers. Lorentz force is availablefor the magnetostatic and eddy current solvers.

Torque The net torque on an object or group of objects. Virtualtorque is available for all solvers. Lorentz torque is avail-able for the magnetostatic and eddy current solvers.

Select Matrix Entries Selects matrix entries to add to the parametric table.

Electrostatic Magnetostatic Eddy Current

Lorentz ForceVirtual ForceLorentz TorqueVirtual TorqueCapacitance Matrix

Lorentz ForceVirtual ForceLorentz TorqueVirtual TorqueInductance Matrix

Lorentz ForceVirtual ForceLorentz TorqueVirtual TorqueImpedance Matrix

File Saves the current setup and exits the module.Edit Deselects all selected objects and toggles the visibility of objects.View Controls and modifies the view displayed in the viewing window.Window Opens, closes, tiles, and cascades viewing windows.Help Accesses the online documentation.

Executive ParametersExecutive ParametersCommands

Executive ParametersMenu Commands


Tool BarMatrix


ForceTorque



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Exiting an Executive Parameters Command> When you finish setting up an executive parameter computation:

1. Choose Exit.2. You are prompted to save your changes.

• Choose Yes to save the parameter setup you have just entered and exit.• Choose No to exit without saving.• Choose Cancel to stay in the current window.

If you saved the parameter setup, a check box appears next to its command on the SetupExecutive Parameters menu.

Tool BarThe tool bar, located just below the menu bar, is primarily composed of the viewing iconsfrom the modeler. To activate a tool bar command, click on the icon whose command youwish to execute. For a brief description of the command, click and hold the left mouse but-ton on the icon.

Click on an icon below to see and explanation of it.



Exiting an ExecutiveParameters Command

Tool BarMatrix


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MatrixChoose Matrix to request that one of the following be computed during the solution:

• Capacitance Matrix (C-Matrix) for electrostatic problems.• Impedance Matrix (Z-Matrix) for eddy current problems.• Inductance Matrix (L-Matrix) for magnetostatic problems.

When you choose Matrix from the pull-down menu, the following window appears:

Matrix computations for magnetostatic and eddy current problems can be set up for con-ductors if:



Exiting an Executive Parame-ters Command

Tool BarMatrix


ForceTorque



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• One of the faces of the conductor is carrying “high” current. “High” current refers to thecurrent going into the conductor.

• An object surrounding the 3D objects is carrying “high” or branch current. This objectcan be a 3D object that encompasses all the objects, or it can be a 2D object whichcuts across the conductors.

• For magnetostatic problems:• There is a voltage source with two terminals in a conductor.• There is a voltage source with a branch terminal in a conductor.• There is a current density source with two terminals in a conductor.• There is a current density source with a branch terminal in a conductor.

> To set up a matrix computation:1. Choose Setup Executive Parameters/Matrix.2. Select the conductors to be included in the matrix using the Select commands.

Only single 3D objects or an object surrounding several 3D objects may beincluded in the matrix setup. For magnetostatic problems, the object must be acurrent source, a current density source, or a voltage source. For electrostaticproblems, the conductor must be a voltage source. For eddy current problems, theobject must be a current source.

3. Choose Yes to include the conductor in the matrix. Choose No to remove aconductor from the matrix.

4. Choose File/Save to save your matrix.5. Choose File/Exit to return to the Executive Commands window.




Tool BarMatrix


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The Return Path for Current

Inductance and impedance are computed after the general field solution, and use differ-ent source assignments than those specified under Boundary/Source Manager.

During each subsolution of the matrix computation, one ampere of current is allowed toflow through a single conductor — a different conductor in each subsolution. No currentflows through the other conductors.

Conductors that are not included in the matrix are treated as non-conducting objects inthe solution process.




Tool BarMatrix


ForceTorque



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ForceChoose Force to compute the force on an object or group of objects.

• In electrostatic models, it’s the net virtual force or Lorentz force.• In magnetostatic models, it’s the net virtual force or Lorentz force.• In eddy current models, it’s the time-averaged virtual force or Lorentz force.

When you choose Force from the pull-down menu, the following window appears:

You can create multiple force setups. Each setup contains objects that are assumed to be




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rigidly connected when the force computation is performed.

> To set up a force computation, do the following:1. Choose Setup Executive Parameters/Force.2. Choose Create to create your setup. A pop-up window appears. The default name

of the setup appears automatically.3. Enter a new name for the setup or accept the default.4. Choose OK. The new setup appears in the Groups field.5. Repeat steps 2 through 4 until you have created the number of setups you require.6. Select the setup.7. Select the objects for which force is to be computed in the setup. Choose each

object’s name, or use the Select commands to pick them.

8. Choose the type(s) of force to be computed:

9. Choose Yes to include the selected objects in the force computation. Choose Noto remove the selected objects from the force computation.

10.Repeat steps 6 through 8 for each setup.11.Choose File/Save to save your settings.12.Choose File/Exit to return to the Executive Commands window.

Note: Objects in a force computation must be able to move freely. If multipleobjects are selected, the system assumes that they are rigidly connected.Physically attached objects must all be selected to obtain meaningful results.

Lorentz Force The Lorentz force acting on the objects.Virtual Force The virtual force acting on the objects.




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TorqueChoose Torque to compute the torque on an object or group of objects about a point.

• In electrostatic models, it’s the net virtual torque or Lorentz torque• In magnetostatic models, it’s the net virtual torque or Lorentz torque.• In eddy current models, it’s the time-averaged virtual torque or Lorentz torque.

When you select Torque from the pull-down menu, the following screen appears:

> To set up a torque calculation:1. Choose Setup Executive Parameters/Torque.2. Choose Create to create your setup. The default name of the setup appears

automatically.




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3. Enter a new name for the setup or accept the default.4. Choose OK to accept the name of the setup. The new setup appears in the

Groups field.5. Repeat steps 2 through 4 until you have created the number of setups you require.6. Select the name of the setup.7. Select the objects for which torque is to be computed in the setup by choosing an

object’s name from the list, or using the Select commands to highlight the object.

8. Choose the type of torque to be computed:

9. Specify the torque:a. Double-click on a point in the problem region to mark the Anchor Point. This is

the starting point of the axis on which the object will rotate.b. Choose Set Anchor Point.c. Double-click on a point in the problem region to mark the End Point. This is the

ending point of the axis on which the object will rotate.d. Choose Set End Point. The axis on which the object will rotate is formed.

10.Choose Yes to include the selected objects in the torque computation. Choose Noto remove the selected objects from the torque computation.

11.Choose File/Save. Skip this step if you do not wish you save your settings.12.Choose File/Exit to return to the Executive Commands window.

Note: Objects in a torque computation must be able to move freely. If multipleobjects are selected, the system assumes that they are rigidly connected.Physically attached objects must all be selected to obtain meaningful results.

Lorentz Torque The Lorentz torque acting on the objects.Virtual Torque The virtual torque acting on the objects.




Tool BarMatrix


ForceTorque


Maxwell 3D — Select Matrix EntriesTopics:

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Select Matrix Entries Select Matrix EntriesUse this command to create a matrix to be solved during the nominal problem solution.

> To select the entries for a matrix:1. Choose Setup Executive Parameters/Select Matrix Entries. The following

window appears:

2. Select a Row entry to highlight it.3. Select a Column entry to highlight it.4. Choose Add to add the selected matrix to the Selected entries list.5. Choose OK to accept the matrix entries or Cancel to cancel the action.

The new matrix entry appears in the Selected entries list.

> To remove an entry from the Selected entries list:1. Select the entry you wish to remove to highlight it.2. Choose Remove.

The entry is removed from the list.


Maxwell 3D — Solution OptionsTopics:

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Setup Solution OptionsAfter conductor types, material attributes, boundaries, and sources have been specified,choose Setup Solution/Options to:

• Select which finite element mesh is used during the solution process.• Manually seed, create, and refine the finite element mesh.• Specify whether fields and/or executive parameters are computed during a solution.• Set the stopping criteria for adaptive field solutions.• Specify the frequency at which eddy current field simulations take place.

When you choose Setup Solution/Options from the Executive Commands menu, the fol-lowing window appears:

If you are solving an electrostatic problem, only the left half of the window will appear.

If you are solving a magnetostatic problem, Magnetic Field Solve is selected by default.

Setup Solution OptionsFinite Element MeshingGeneral ProcedureStarting MeshManual MeshMeshmaker Tool Bar Func-tions

Meshmaker CommandsSolver TypeFrequencySolution TypesSolve For Fields and Param-eters

Adaptive AnalysisConduction Percent Errorand Analysis




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Finite Element MeshingRepresenting an electric or magnetic field over a relatively large region is a fairly difficulttask. Fields cannot be accurately described with a single polynomial expression that cov-ers the entire problem region. The approach taken by Maxwell 3D is to use finite elementanalysis to subdivide the problem region into many smaller regions (tetrahedra) wherefields may be accurately computed.

Need for a Fine Mesh

Although this implementation of the finite element method is largely transparent to usersof the software, a general understanding of it is necessary to ensure that the field solutionis as accurate as possible for a given amount of computing resources.

Maxwell 3D directly computes only electric and magnetic fields at the nodes (vertices) oftetrahedra. To obtain values for the electric or magnetic field at all other locations, it inter-polates the field from the nodal values of the finite element mesh. For example, in theelectrostatic field solver, the value of the electric potential is stored at each node; poten-tials at locations inside the tetrahedra are interpolated from the nodal values.

There are a number of factors that facilitate the need to refine the mesh:

• If the tetrahedra are too large, the fields inside the tetrahedra cannot be interpolatedaccurately. A large tetrahedron located where the field gradients are mild would havesimilar interpolation error to much smaller tetrahedra in a strong gradient region. Sincewe do not know where the strong gradients are going to be prior to solving theproblem, the initial meshes are seldom adequate.

• If the field in the vicinity of a tetrahedron is changing too rapidly, the fields inside thetetrahedra cannot be interpolated accurately.

• The shape of the tetrahedron affects the interpolation errors. More complex shapeslead to excessively large meshes. Refining large meshes lead to even larger meshes.

The meshmaker relies on adaptive refinement to focus the computational effort exactlyinto regions that require it. The optimal mesh for a structure is one that has enough tetra-hedra to accurately represent a field solution but not so many that the available computingresources are overwhelmed. The initial mesh that is generated for a structure is rarely theoptimal mesh. The mesh must be refined — that is, it has to be divided into more tetrahe-dra.


Need for a Fine MeshMeshmaker Sizing Limits(Min D)

General ProcedureStarting MeshManual MeshMeshmaker Tool Bar Func-tions






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The Setup Solution/Options command lets you control the mesh refinement process.There are two ways to accomplish this task:

• Adaptive mesh refinement. Refines the mesh iteratively in regions where the energyerror is high. You set the criteria that controls mesh refinement during an adaptive fieldsolution. Many problems can be solved using only adaptive refinement.

• Manual mesh refinement. You explicitly specify where the mesh is refined. This isuseful when you know where high-error areas such as air gaps or discontinuities in acore are located.

Use either strategy or a combination of both to best refine the mesh.

Meshmaker Sizing Limits (Min D)

Like the 3D Modeler, the 3D Meshmaker uses the concept of Min D as the foundation forconstructing the finite element mesh.

Min D is defined to be the distance between a point and a line that is small enough so thatthe point may be considered to be resting on the line. Currently, Min D is set to be 10-7

times the smallest dimension of the problem region. If the distance between two points issmaller than Min D, the points are considered coincident.

The tolerance used in geometry calculations are based on Min D. For example, a point isconsidered to be on a plane if the perpendicular distance from the point to the plane issmaller than Min D.


Need for a Fine MeshMeshmaker Sizing Lim-its (Min D)

General ProcedureStarting MeshManual MeshMeshmaker Tool Bar Func-tions






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General Procedure> To specify solution criteria for a model, follow this general procedure:

1. Choose Setup Solution Options.2. Specify the solution parameters, including:

• The starting mesh.• Whether you want to manually refine the mesh.• The solver type.• For eddy current solutions, the frequency at which fields and source currents

oscillate.• Whether fields and executive parameters are computed during the solution.• Whether an adaptive analysis is performed.• The percent refinement per pass.• The stopping criterion for adaptive field solutions.• For adaptive magnetostatic solutions, the conduction percent error and analysis.

3. Choose OK to save the solution criteria and return to the Executive Commandsmenu.

Note: The process of computing a field solution is an iterative one in which the sys-tem converges on a field pattern that satisfies Maxwell’s equations. In gen-eral, accept the default stopping and refinement criteria for the first few fieldsolutions. Then, check their convergence to see if the stopping criteria needto be adjusted.







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Starting MeshChoose one of the following to specify the type of mesh to start the solution process.

Initial

The initial, coarse mesh is automatically created at the start of the solution process. Asmuch as possible, it uses the vertices (object points) of the geometry as the vertices ofelements in the mesh. In general, you should perform an adaptive analysis if you selectInitial Mesh. Because the elements of an initial mesh are relatively large, a non-adaptivesolution that uses the initial mesh is not likely to be an accurate one.

Current

The finite element mesh that was most recently refined. To take advantage of a previousadaptive analysis or manual mesh refinement, choose this as the starting mesh.

> If you are generating the first solution for a project, follow these guidelines to decidewhat type of mesh to use:• If the geometry is simple, you can optionally seed the mesh to give the adaptive

meshing process a head start. For each object, use a seed value that is approximatelyone-eighth of that object’s longest dimension.

• If the geometry is complex, even the smallest amount of seeding may result in a meshthat is too complicated. Start with an unseeded initial mesh and adaptively refine it.

• Manually refine the mesh inside perfect conductors to make the solution convergemore quickly.

• For all geometries, perform at least one adaptive solution to further refine the mesh.

> Use the following guidelines for subsequent refinements:• Use the current mesh whenever you want to generate a solution based on the last

mesh that was created — or to further refine an existing solution.• Use the initial mesh to discard any previous manual or adaptive mesh refinements

and start over from scratch.

Setup Solution OptionsFinite Element MeshingGeneral ProcedureStarting Mesh

InitialCurrent

Manual MeshMeshmaker Tool Bar Func-tions






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Manual MeshChoose Manual Mesh to manually refine the finite element mesh in areas of interest. Usethis command to:

• Seed the mesh with extra points and save the seeding.• Refine the mesh inside geometric objects or on a surface.• Change the attributes of the mesh, such as the display type or plot mode.

When you choose Manual Mesh, the following window appears:

Note: The saved manual mesh automatically becomes the Current Mesh.







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Meshmaker Tool Bar FunctionsThe tool bar, located just beneath the menu bar, provides icons that can be used to exe-cute certain commands. Click on the icon to activate its command. To see what the com-mand does without activating it, click on the icon and hold down the left mouse button.

The Meshmaker tool bar is shown below.

Meshmaker CommandsThe following menus appear in the Meshmaker’s menu bar:

After the mesh is completed, you may need to refine the mesh to obtain more accurateresults that will converge faster. The Refine menu is enabled only after a mesh is created.The commands in the refine menu allow you to:

• Refine the mesh of the face or surface of an object.• Refine the mesh of an object or box.

FIle This menu allows you to save your mesh, create a new mesh, open andclose a previous mesh, and exit the Meshmaker.

Edit Select the bodies and faces of objects.View This menu is identical to the one in the 3D Modeler.Coordinates This menu is identical to the one in the 3D Modeler.Seed Seed objects, thus making the finite element mesh more able to give an

accurate solution.Mesh Makes, displays, and deletes meshes.Refine Refines an object face, surface, or other attribute of an object.Window This menu is identical to the one in the 3D Modeler.Help Accesses the online help and documentation.







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• Define or clear the meshing region.

When you choose Refine from the menu bar, the following menu appears:

When refining the mesh on an object or face, the 3D Meshmaker selects all the tetrahedraon the geometric entity and finds the largest length, area, or volume. After it finds the larg-est value, the 3D Meshmaker refines the mesh until the value of the length, area, or vol-ume reaches the value you specify. When specifying refinements for your objects andsurfaces, you may refine the following aspects of the mesh:

By Length Refines the length of all the tetrahedra until they are below the enteredValue.

By TriangleArea

Refines the area of the triangles of the tetrahedra until they are belowthe entered Value.

By Volume Refines the volume of the tetrahedra until they are below the enteredValue.

By SkinDepth

Refines the skin depth region by the calculated Skin Depth value.







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Solver TypeYou can specify which type of solver to use to solve the problem. The Direct solver is thedefault, and will always converge to a solution.

The ICCG (incomplete conjugate gradient solver) solver is faster for large matrices, butoccasionally fails to converge (usually on magnetic problems with high permeabilites andsmall air-gaps). When you select the ICCG option, you must enter a value for the LinearResidual.

Residuals

The residual is a normalized measure of how close a field solution comes to satisfying theelectromagnetic field equation that is being solved. The solution from each iteration issubstituted back into the field equation. If it happens to be the exact solution, the residualis zero. Otherwise, the residual is non-zero and a small correction is added to the solutionprocess for the next iteration. The iterative solution process continues until the residual isless than the specified target value.

The residual does not affect the finite element mesh. The system attempts to reduce theresidual to the target value while using the same mesh.

Linear Residual

ICCG solvers only.

The Linear Residual specifies how close a field solution must come to satisfying theappropriate form of Maxwell’s equations.

In most cases, accept the default value.

Nonlinear Residual

For magnetostatic problems that contain nonlinear materials, there is also a Nonlinearresidual. The nonlinear residual specifies how close a magnetostatic field solution mustcome to satisfying the appropriate form of Maxwell’s equations.


Meshmaker CommandsSolver Type

ResidualsLinear ResidualNonlinear Residual

FrequencySolution TypesSolve For Fields and Param-eters





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FrequencyEddy Current

The frequency at which source currents and external fields oscillate. Frequency can bespecified in hertz, kilohertz, megahertz, or gigahertz — click on the button next to the Fre-quency field, and select the units.

The frequency that you choose affects the simulated loss. For example, at high frequen-cies, the skin effect increases the series resistance by forcing current to the outside ofconductors. The hysteresis loss associated with materials that have a non-zero imaginarypermeability also increases with frequency.

Note: If you change the units, the Frequency field changes to retain the originalfrequency.



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Solution TypesMagnetostatic problems only.

Select the types of solutions to generate.

• For magnetostatic solutions, select Magnetic Field Solve to instruct the solver togenerate an appropriate solution.

• For conduction solutions, select Conduction Solve to instruct the solver to generatethe conduction solutions.

Solve For Fields and ParametersSelect the field quantities to be computed during the solution process:

In general, leave both of these options selected.

Fields Solves for the model’s electric or magnetic fields.Parameters Computes any executive parameters (force, torque, capacitance,

impedance, inductance, and so forth) or post-processing macros thatwere requested via the Setup Executive Parameters command.


Meshmaker CommandsSolver TypeFrequencySolution TypesSolve For Fields andParameters





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Adaptive AnalysisSelect Adaptive Analysis to iteratively refine the mesh during the solution. The generaladaptive solution process appears below. The electrostatic solution process, magneto-static solution process, and eddy current solution process differ slightly from this model.

Adaptive Solution

In general, an adaptive field solution follows this process:

1. Maxwell 3D generates a field solution using the mesh type that you specify. (Theinitial mesh is generated before the field solution begins.)

2. It computes the energy and residual, and compares them to the specified solverresidual. When the residual is less than the specified value, the solution is done.

3. The simulator computes the percent error, which is the percentage of the totalsystem energy associated with the residual. The process stops if it is less than thespecified value, or if the number of requested passes has been performed.

4. New tetrahedra are added to the finite element mesh in areas of high error.5. Another solution is generated using the refined mesh, and the entire process

(solve — error analysis — refine) repeats until the stopping criterion is satisfied.

Start field solution

Generate initial mesh Compute field energy

Yes

Refine meshNo

Perform error analysis

Stop field solution

and residual

Stopping

criterion met?



Adaptive AnalysisAdaptive SolutionNon-Adaptive SolutionPercent Refinement PerPass

Stopping CriterionConduction Percent Errorand Analysis




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Non-Adaptive Solution

A non-adaptive solution only follows steps 1 through 3 on the previous page. It does notrefine the mesh.

Percent Refinement Per Pass

Determines how many tetrahedra are added after each iteration of the adaptive refine-ment process. For instance, entering 10 in this field causes the ten percent of the tetrahe-dra with the highest error to be refined. Generally, accept the default value.

Stopping Criterion

Maxwell 3D breaks out of the adaptive solution cycle when one of the following criteria ismet.

Number of Requested Passes

Specify the maximum number of refinement cycles (adaptive passes) that you want Max-well 3D to perform. Typically, use a value between three and five.

The size of the finite element mesh — and the amount of memory required to generate asolution — grows with each adaptive refinement of the mesh. Setting the number ofpasses too high can cause the software to request more memory than is available.

Percent Error

Specify the acceptable Percent Error of the solution. This lets you control the solutionaccuracy. In general, accept the default for this field. Smaller values produce slower, moreaccurate solutions while larger values produce faster, less accurate solutions.

The system stops the adaptive refinement process when both of the following calculatedvalues are less than your specified values:

• The percent error energy. Maxwell 3D computes the total field energy and the energycontributed to this total by the error residual. The percent error energy is thepercentage of total energy that the residual contributes. A small percent error energyindicates that only a small amount of the total energy is associated with the residual(error) and that the solution is highly accurate.

• The percent change in energy between adaptive passes. Small energy changesbetween passes indicate the solution has converged.



Adaptive AnalysisAdaptive SolutionNon-Adaptive SolutionPercent Refinement PerPass

Stopping CriterionConduction Percent Errorand Analysis




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Conduction Percent Error and AnalysisAdaptive magnetostatic solutions

Select Conduction Solve to generate a conduction solution.

As in the adaptive solution, you are expected to specify the percent error of the conduc-tion current solution, which is computed as part of the adaptive magnetostatic solutionprocess. An adaptive conduction current solution uses a solve — error analysis — refinecycle that is similar to the general adaptive solution process. When the percent error ofthe conduction solution falls below the specified value, the conduction solution stops andthe adaptive magnetostatic field solution begins.

In most cases, use the default error value. Use a higher error value if your model hascomplicated conduction paths with sharp bends and corners or changes in cross-sec-tional areas.

Convergence of the Conduction Solution

To determine whether you’ve specified an appropriate percent error, monitor the conduc-tion current solution when you solve for fields. An adaptive conduction simulation shouldconverge to a stable value within five or six passes.

> To view convergence statistics on the conduction solution:• Choose Convergence.

If the conduction solution fails to converge, specify a higher Conduction Percent Error.Solve the problem again, noting the convergence. Repeat this procedure, increasing thepercent error of the conduction solution until it converges within five or six passes.




Convergence of the Con-duction Solution




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Suggested ValuesChoose this button to reset all fields to their suggested values. Doing so gives you a set ofsolution options that enables you to compute a reasonably accurate adaptive solution.

In general, use the suggested values for the first set of adaptive solutions. Then, examinethe convergence data to see if the solution has converged.

> If the solution has not converged, do the following:1. Modify the default solution criteria. Increase the number of requested passes and

do one or more of the following:• Increase the percent refinement per pass.• Specify a higher value for the conduction percent error.• Decrease the percent error.

2. Solve the problem using the updated solution criteria.







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Glossary of TermsDescription of AnalysesCommon Workaroundsand Fixes

Meshing ErrorsThe Meshmaker is very robust and will generate meshes even for extreme geometries.However, when attempting to mesh a combination of ambiguous models, the Meshmakermay fail. When this happens, the Meshmaker analyzes the model and generates a reportof the error encountered. This report is saved to model_analysis.html in the projectdirectory. You may open this file with any web browser or software capable of loading.html files.

Keep the following points in mind when the mesh fails.

• A single error in the model rarely causes the mesh to fail; it is usually a combination oferrors.

• One modeling feature may be flagged as multiple errors. For example a very smallfillet could be flagged as a narrow face, very short edge, and small face on a largeshell. So try to treat the warnings as symptoms of an underlying feature and to locatethe cause.

The following sections describe the analyses performed on the model and how to identifythe flagged anomaly. They explain the terms used in the report, common sources of theproblems, and the known workarounds.

Glossary of Terms

The following terms may appear in the report generated by the Meshmaker.

Body

Bodies are objects that make up the model. Maxwell 3D permits only one contiguous vol-ume, or lump, per body. Imported models that have multi-lumped bodies will be convertedto single lumped bodies by the 3D Modeler.

Lump

A lump is a contiguous volume that comprises a body and is constructed of shells.



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Shell

Shells are the surfaces of solids and are constructed of faces. Most objects consist of onlyone shell. Cubes, cylinders, spheres, a box with a hole drilled through it, annular cylin-ders, and so forth are examples of single shell objects.

If a small void exists in the middle of the body, and the shell associated with the void doesnot touch any portion of the external shell, the object will have two shells. If you subtractsolid A from solid B and solid A was completely contained in solid B, then you will get atwo shell body. Each time you subtract a solid that is fully contained inside another withouttouching any existing shell you will get one more shell.

The following figure consists of three shells. It was created by subtracting two cylindersfrom the box in which they were contained.



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Face

Faces are portions of object surfaces and are constructed of loops. Faces can be planar,conical, spherical, toroidal, cylindrical, or splines. For example, a typical cylinder consistsof three faces, two planar circular end faces, and one cylindrical face, while a sphere ortorus consists of one face and a cube six faces.

Loop

A loop is the perimeter of a face much like a shell is the boundary of a body and is con-structed of edges. Most faces consist of a single loop; however, if portions of the perime-ter form disconnected, closed loops then multiple loops are formed.

For example, in the following figure, the face of the cylinder consists of two loops, one atthe top and one at the bottom. Likewise, the square plate with the hole consists of twoloops, one for the outer square and one for the inner circle.

Edge

Edges are portions of loops. A rectangular face has four edges, a circular face one edge.Curiously a toroidal face has two edges.



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Aspect Ratio

Aspect ratios is a measurement of how “narrow” a face is or how “thin” a body is. Thebody aspect ratio is defined to by:

where:

• S is the surface area.• V is the volume.

For example, the aspect ratio is 1 for sphere and 0.723 for a cube.

Similarly for sheet objects and faces the aspect ratio is defined by:

where:

• A is the area.• p is the perimeter.

For example, the aspect ratio is 1 for circles and 0.785 for squares.

6 π V

S3

---------

4π A

p2

-----



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Description of Analyses

Three kinds of analyses are performed on the model when the Meshmaker fails. They arecalled Model Analysis, Contact Analysis, and Proximity Analysis.

In the report produced by these analyses, many coordinates will be printed in the form:

setcurpos [0.2400e001 , 0.44321e-001 , 0.33332e-001]

You can cut and paste this line from your browser into the command prompt of the 3DModeler. The cursor moves the specified location and you can zoom in to see the modelin the vicinity of the specified coordinates. This method is recommended to avoid thetedium of typing and mistyped coordinates. You can scroll back and re-execute any com-mand typed in the command window. This is useful if the current cursor position changesduring the zoom and you want to re-enter the coordinates.

The reports identify the faces by id numbers, the body to which the face belongs, and thecorners of the bounding boxes. The faces can be highlighted and displayed in the 3DBoundary Manager by their id numbers using Edit/Select/By Name.

For those cases where one modeling feature is flagged as multiple errors, check for verti-ces identified by their id numbers. If an id number is mentioned for a vertex it would beunique for that vertex. Otherwise it would be quite tedious to check if the same point isreferred to by many errors by comparing the x-, y-, and z-coordinates, since the coordi-nates are double precision numbers often differing in the last few decimal places.

Model Analysis

When the Meshmaker performs a Model Analysis, the objects in the model are analyzedone at a time. In this test the topological structure of the entire model is examined, andrelevant figures like volume, surface area, and perimeter are calculated. From this, verysmall objects, very narrow faces, and so forth can be located. These errors are describedin detail in the following sections.

Every error reported can be traced to a specific model feature. Keep in mind that some-times a single problem can generate multiple errors.



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Bodies with negative volumes: “A body with negative volume is found”

This happens when face normals are oriented in the wrong direction, creating a kind ofinside-out body, or when a body is not closed. This error cannot occur on models drawn inthe 3D Modeler. It only occurs when .sat files generated by other software packages areimported into the 3D Modeler.

If this error occurs, delete the solid and redraw it correctly. If the model was generated bythird party software, then the process of model generation and translation must be studiedto localize the problem.

Bodies with negative face areas: “A Face with negative area is found”

This happens when loops are oriented in a wrong way or the face is not properly closed.Treat it the same way bodies with negative volumes are treated.

Low aspect ratio bodies and faces: “A very thin body is found” or “A very narrowface is found”

This happens when there is an aspect ratio violation.

Common workarounds are to use sheet objects instead of solid objects wherever possibleand to redraw the model with snaps turned on.

Large body volume ratios: “Huge differences found in body volumes found”

This happens when the volume ratio of the largest body to the smallest exceeds a thresh-old. The report names the bodies and includes their volumes and the ratio.

Check to see if the small bodies are necessary to model the problem or if the large bodiesneed to be that large.

Large shell area ratios: “Two shells of a body have huge differences in surfaceareas”

This happens when the surface area ratio of the largest shell on a body to the smallestshell on the body exceeds a threshold. If small voids are present in a large body, theirshell surface areas exhibit large differences.

Check to make sure that the small voids are really model objects and not artifacts or left-overs from translation.



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Large face area ratios: “Two faces of a shell have huge differences in areas”

This happens when there are large and small faces in the same shell. This might be dueto very thin objects, or due to boolean operations of slightly misaligned objects.

Check to see if the small face is a designed feature or an artifact of boolean operations.

Large loop length ratios: “Two loops on a face have huge differences in perimeterlengths”

This happens when you have features like small holes or stubs on a large face. This isanalogous to the shell surface areas error.

Again, check to see if the small features are by design or are even needed.

Small edges on a loop: “Two edges on a loop have huge differences in lengths”

This happens when the ratio of the length of the longest edge to that of the shorted edgein the same loop exceeds some threshold.

Redraw the region if possible.

Very small body or edge: “A body in the model is very small” or “An edge in themodel is very small”

This happens when there are very small bodies or edges in the model. The Meshmakercannot mesh these items. These small edges might be due to boolean of misalignedobjects or if you have turned off snap while drawing the model.

Locate the item and see if it is really needed.



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Meshing ErrorsGlossary of TermsDescription of AnalysesCommon Workaroundsand Fixes

Contact Analysis

When the Meshmaker performs a Contact Analysis, all the triangles on each face areanalyzed. All surface triangle edges and surface triangles that are smaller than a certainfraction of the maximum edge or maximum surface triangle area on that face get reported.This draws attention to the regions where misaligned objects have created small edgesand triangles. These triangles are marked with the header Small triangle or Small edge.

While generating the mesh, if two objects are in contact, the common area of contactmust be meshed in a compatible manner. So a situation can arise in which two objectsthat can be meshed easily are juxtaposed in such a way that the resulting model hasmeshing difficulties. For example, take two cubes that touch each other on a face exactly,say at the z=0 plane. If one cube is shifted along the x or y direction by a very smallamount but larger than the snapping tolerance, the Meshmaker could fail, or create a badmesh.

Another situation in which small triangles and edges can be created is when the Mesh-maker tries to correct problems in surface triangulation. When it finds vertices, edges,faces, and so forth that approach each other very closely but do not actually intersect, theMeshmaker tries to stitch them together. While this may correct misalignments and prob-lems due to floating point errors in the translation process, it may also, in some situations,fail to correct the problem. When the Meshmaker attempts to correct these problems andfails, it creates many small triangles and edges.



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Proximity Analysis

When the Meshmaker performs a Proximity Analysis, the distances between bodies areexamined. If they are found to be less than the 3D Modelers tolerance, around 0.1 partper billion, they are considered to be “in contact” and left alone. If they fall between manu-facturing tolerances (100 parts per million to 1 ppm) and the 3D Modeler’s tolerance, theMeshmaker attempts to stitch the surface triangulation in the neighboring regionstogether to correct the error. For this purpose it uses a “snapping” distance of 500 timesthe 3D Modeler's tolerance. The first fifty anomalies found are stored and reported as theresults of Proximity Analysis. This analysis has to be done for all models and most of thetime the errors are found and fixed without any problems.

The most common and easily fixed proximity error is the type Vertex-Vertex. Here a ver-tex of some body comes very close to a vertex of another body but the distance betweenthem is more than the tolerance of the 3D Modeler. If the distance is less than the snap-ping distance tolerance they will be “snapped” together. Otherwise it could lead to prob-lems in surface recovery. Vertex-edge and Vertex-face are similar to Vertex-Vertex, buthere a vertex comes close to an edge or face of a model. This usually happens when youhave true surfaces making a tangential contact with other surfaces.

Other possible errors are Edge-edge or Face-edge.

Common Workarounds and Fixes

Here are a few common workarounds and fixes to consider if you are having problemsmeshing:

• Redraw the model.• If the model is imported, check if the original software package has functions that

could eliminate the problems.• Turn snapping on if it was off.• Avoid extreme geometries. For example eddy currents can be simulated using

impedance boundary conditions. So instead of creating a very thin solid object, use animpedance boundary on a 2D sheet object or on an object surface.


Maxwell 3D Meshmaker — Seed MenuTopics:

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Seed MenuSeeding is an optional step in creating a finite element mesh and is recommended onlyfor use in seeding parametric sweeps. When you seed an object, the mesh will follow theseeded points and form a series of triangles from which the solution will be computed.The Seed menu is disabled after the mesh is made. Seeding can be considered an “unat-tended’ refinement. This menu is functionally equivalent to the Refine menu, which offersbetter control and feedback over the refinement process.

This menu allows you to:

• Seed faces of objects in your model.• Seed an object or box.• Get information about your seeding.• Save or delete a seeding you have created.

When you choose Seed from the menu bar, the following menu appears:

Seed MenuMesh SeedingSeed CommandsSeed/Object Face

Seed/Object Face/By Vol-ume

Seed/Object Face/By Tri-angle Area

Seed/Object Face/ByLength

Seed/Object Face/BySkin Depth

Number of LayersSeed/Object

Seed/Object/By VolumeSeed/Object/By Length

Seed/BoxSeed/Box/By VolumeSeed/Box/By Length

Seed/Seeding InfoSeed/DeleteSeed/Delete AllSeed/Save



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Mesh SeedingSeeding provides additional points at which the vertices of the mesh tetrahedra meet. Thelarger the number of seeds, the more dense the finite element mesh, and the more accu-rate the solution.

You may seed the following aspects of the mesh:

Seed CommandsThe following commands are available in the Seed menu:

By Length Seeds the mesh until length of all the edges of the tetrahedra are lowerthan the entered Value.

By TriangleArea

Seeds the mesh until the area of each of the triangles in the mesh arelower than the specified Value.

By Volume Seeds the mesh until the volume of each of the tetrahedra are lowerthan the entered Value.

By SkinDepth

Seeds the mesh until the number of tetrahedra in the skin depth arelower than the entered Value.

Object Face Seeds the selected faces of objects.Object Seeds an entire object, including its interior.Box Seed a box or rectangular object.Seeding Info Displays the information on your current seeding.Delete Deletes the seeding of an object.Delete All Deletes the seedings of all the objects in your model.Save Saves your seeding.





Seed/Object Face/By SkinDepth







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Seed/Object FaceUse these commands to seed the face of an object. If an object is selected, all of its faceswill be seeded. Choose one of the following from the Seed/Object Face menu:

Seed/Object Face/By Volume

Choose this command to seed the face of an object.

> To seed the face of an object:1. Select the face of an object to seed using the selection commands.2. Choose Seed/Object Face/By Volume. The Seed/Refine controls window

appears.3. Optionally, select Maximum number of elements to be added to specify the

maximum number of elements added. The software will not exceed this value. Ifyou select this, enter the maximum number of elements in the edit field on theright.

4. Select Maximum element volume to specify the maximum volume of theelements touching the selected faces. The Meshmaker refines all the elementstouching the selected faces until their volume is equal to or less than the volumeyou specify. If you select this, enter the maximum volume of the elements in theedit field on the right.

5. Choose OK to accept your values or choose Cancel to cancel the action.6. Choose Seed/Save to save the seed refinement settings.

When the mesh is generated, the refinement criteria you have specified will be used. Youmay generate the mesh manually using Mesh/Make.

By Volume Refines the volume of the tetrahedra touching the selected facesuntil their volume is below the specified value.

By Triangle Area Refines the area of the triangles (of the tetrahedra touching theselected faces) until their area is below the specified value.

By Length Refines the length of all the tetrahedra touching the selected facesuntil their length is below the specified value.

By Skin Depth Refines the surface triangle length of all tetrahedra within thespecified skin depth.


Seed/Object Face/ByVolume










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Seed/Object Face/By Triangle Area

Choose this command to seed the area of the triangles of the tetrahedra until they arebelow the entered refinement parameters.

> To seed the volume meshing on the face of an object:1. Select the face of an object to seed using the selection commands.2. Choose Seed/Object Face/By Triangle Area. The Seed/Refine controls window



4. Select Maximum surface triangle area to specify the maximum area of thesurface triangles (the faces of the tetrahedra touching the surface). TheMeshmaker refines all the surface triangles until their area is equal to or less thanthe area you specify. If you select this, enter the maximum area of the triangles inthe edit field on the right.

5. Choose OK when you have finished specifying the refinement criteria.6. Choose Seed/Save to save the seed refinement settings.













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Seed/Object Face/By Length

Choose this command to seed the length of all the tetrahedra until they are below theentered refinement parameters.

> To refine the length meshing on the face of an object:1. Select the face of an object to seed using the selection commands.2. Choose Refine/Object Face/By Length. The Seed/Refine controls window



4. Select Maximum element length to specify the maximum length of the edges ofthe tetrahedra touching the surface. The Meshmaker refines the edges of thetetrahedra touching the selected faces until they are equal to or less than thelength you specify. If you select this, enter the maximum edge length in the editfield on the right.














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Seed/Object Face/By Skin Depth

Choose this command to seed the skin depth of the mesh on the object until it is belowthe calculated refinement parameters.

> To seed the skin depth meshing on the face of an object:1. Select the face of an object to refine using the selection commands.2. Choose Seed/Object Face/By Skin Depth. The following window appears:

3. Optionally, select Maximum number of elements to be added to specify themaximum number of elements added. The software will not exceed this value. Ifyou select this, enter the maximum number of elements in the edit field on theright.












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4. Enter the number of layers perpendicular from the object’s surface to add points inthe Number of layers of elements field. The Meshmaker adds an equivalentnumber of points to each layer as it added on the surface. For example, if theMeshmaker added 10 points to satisfy the Surface triangle length of the trianglemesh on the surface, it will add 10 points to each layer.

5. Enter the skin depth within which to refine the mesh in the skin depth field. Youmay also calculate the skin depth using the Calculate Skin Depth command. Theresults of that calculation appear in the skin depth field.

6. Enter minimum edge length of the surface mesh in the Surface triangle lengthfield. The Meshmaker refines the surface triangle mesh (the faces of the tetrahedratouching the surface) until their edge length is equal to or less than the edge lengthyou specify.

7. Choose Calculate Skin Depth. A new window appears. Skin depth is based on:

where:• µ0 is the permeability, in henries/meter.• µr is the relative permeability, in henries/meter.• σ is the conductivity, in siemens• f is the frequency, in hertz.

8. Enter the following values in their respective fields to define the skin depth:

9. Choose OK. The window closes. New values appear in the Edge Length list,describing the seeding parameters.

10.Choose OK to accept your values or choose Cancel to cancel the action.11.Choose Seed/Save to save the seed refinement settings.


Relative Permeability Enter the relative permeability.Conductivity Enter the conductivity of the skin depth in mhos/m.Frequency Enter the frequency.

δ 1

πµ0µrσf--------------------------=












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Number of Layers

The Meshmaker creates a series of layers that are planes parallel to the object face, andspaced within the specified skin depth. For each point on the surface of the face a seriesof points (P0, P1, P2, ..., Pn) are added to the mesh, where n is the number of layers. P0is the point on the surface and the distance from P0 to Pn is the skin depth. The points arespaced in a non-uniform manner, with the distance between them decreasing in a geo-metric progression, as you move from Pn to P0.

For example, if:

then:

The skin depth seeding/refinement first satisfies the surface triangle edge length criterion,then introduces the series of points to each additional layer. If a limit has been placed onmesh growth, one of the following happens:

• The limit is set high enough to complete skin depth refinement.• The limit is set high enough to satisfy the surface triangle edge length criterion, but not

high enough to complete the depth seeding.• The limit is not set high enough to satisfy even the surface triangle edge length

criterion.

Because seeding or refining by skin depth can add many points, seed the surface of theobject using Seed/Object Face/By Length to get an accurate count of the number ofpoints the Meshmaker will add when seeding or refining by skin depth. This allows you toreach the surface edge length criterion first and get an idea of the number of elements inthe mesh and the number of points on the surfaces before proceeding to skin depth seed-ing.

Skin Depth: 12 mm.Number of layers: 4

Distance [P0,P1]: 0.8 mm.Distance [P1,P2]: 1.6 mm.Distance [P2,P3]: 3.2 mm.Distance [P3,P4]: 6.4 mm.Distance [P0,P4]: 0.8 + 1.6 + 3.2 + 6.4 = 12 mm












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Seed/ObjectUse these commands to seed the mesh of a selected object. Points will be added to boththe surface and the interior of the object. Choose one of the following from the Seed/Object menu:

Seed/Object/By Volume

Choose this command to seed the object by the volume of its elements. This commandrefines the volume of the tetrahedra until they are below the entered refinement value.

> To seed the mesh:1. Select an object to seed using the selection commands.2. Choose Seed/Object/By Volume. The Seed/Refine controls window appears.3. Select Maximum number of elements to be added to specify the maximum

number of elements added. The software will not exceed this value. If you selectthis, enter the maximum number of elements in the edit field on the right.

4. Select Maximum element volume to specify the maximum volume of theelements inside the selected objects. The Meshmaker refines the elements untiltheir volume is equal to or less than the volume you specify. If you select this, enterthe maximum volume of the elements in the edit field on the right.



By Volume Refines the volume of the tetrahedra until their volume is below thespecified value.

By Length Refines the length of all the tetrahedra until their length is below thespecified value.












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Seed/Object/By Length

Choose this command to seed the object by the length of its elements. This tells thesolver to refine the length of all the mesh elements until they are below the enteredRefinement Value.

> To seed the mesh:1. Select an object to seed using the selection commands.2. Choose Seed/Object/By Length. The Seed/Refine controls window appears.3. Select Maximum number of elements to be added to specify the maximum

number of elements added. The software will not exceed this value. If you selectthis, enter the maximum number of elements in the edit field on the right.















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Seed/BoxUse these commands to seed an arbitrary box in space. This is useful for seeding airgaps or portions of objects. The box can cut across multiple objects. Choose one of thefollowing from the Seed/Box menu:

Seed/Box/By Volume

Choose this command to seed the volume of a box.

> To seed a box by volume:1. Choose Seed/Box/By Volume. New fields appear in the side window.2. Click on a point in the view window to define the base vertex of your box or enter

the coordinates of the point in the coordinates fields.3. Choose Enter to accept this point or Cancel to cancel the action.4. Enter the size of the box in the Enter box size fields.5. Choose Enter to accept this point or Cancel to cancel the action. When you enter

the size of the box, the Seed/Refine Controls window appears, displayinginformation about the current tetrahedra and the volume of the mesh.

6. Select Maximum number of elements to be added to specify the maximumnumber of elements added. The software will not exceed this value. If you selectthis, enter the maximum number of elements in the edit field on the right.

7. Select Maximum element volume to specify the maximum volume of theelements inside the specified box. The Meshmaker refines the elements until theirvolume is equal to or less than the volume you specify. If you select this, enter themaximum volume of the elements in the edit field on the right.
















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Seed/Box/By Length

Choose this command to seed the elements in a selected region of space by the length oftheir longest edge.

> To seed a box by length:1. Choose Seed/Box/By Length. New fields appear in the side window.2. Click on a point in the view window to define the base vertex of your box or enter

the coordinates of the point in the coordinates fields.3. Choose Enter to accept this point or Cancel to cancel the action.4. Enter the size of the box in the Enter box size fields.5. Choose Enter to accept this point or Cancel to cancel the action. When you enter

the size of the box, the Seed/Refine Controls window appears, displayinginformation about the current tetrahedra and the volume of the mesh.


7. Select Maximum element length to specify the maximum length of the edges ofthe tetrahedra inside the box. The Meshmaker refines the edges of the tetrahedrauntil they are equal to or less than the length you specify. If you select this, enterthe maximum edge length in the edit field on the right.














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Seed/Seeding InfoUse this command to display the type, value, and names of the seeding you have created.

> To see the information on your seeding:1. Choose Seed/Seeding Info. The Seeding Information window appears.2. Choose OK to return to the Meshmaker.

You return to the main meshmaker window.

Seed/DeleteUse this command to delete a current seeding. You can reseed your object after you havedeleted the previous seeding.

> To clear your model of its seeding:1. Choose Seed/Delete. A Seeding Parameters window appears.2. Select the seeding to delete.3. Choose OK to delete the seeding or choose Cancel to cancel the action.

Seed/Delete AllUse this command to delete all the seedings for all the objects in your model.

> To remove all the seedings from your model:• Choose Seed/Delete All.

Seed/SaveUse this command to save the seeding.

> To save your seeding:• Choose Seed/Save.

Your seeding is now saved. Once the seeding has been saved, you can choose Mesh/Make to generate the mesh to fit the seeding. Note that once a mesh has been gener-ated, the Seed commands are greyed out and inactive, and the seeding information can-not be accessed.











Maxwell 3D — Mesh MenuTopics:

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Mesh MenuAfter you have seeded your object, you must create the finite element mesh from whichthe variables and values of your model will be computed.

The mesh menu allows you to:

• Create or delete a mesh.• Display information such as the number of tetrahedra and volumes in your object.• Change the display attributes for the mesh.

When you choose Mesh from the menu bar, the following menu appears:

Mesh MenuMesh Commands

Mesh/MakeSettings for Initial SurfaceTriangulation

Mesh/DeleteMesh/Mesh InfoMesh/Show MeshMesh/Display Parameters



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Mesh CommandsThe following commands are available from the mesh menu:

Mesh/Make

Use this command to create a finite element mesh from the seedings. If seeds have beendefined, they will be used to further refine the mesh.

Settings for Initial Surface Triangulation

Create a mesh using the Settings for Initial Surface Triangulation window.

> To create a mesh:1. Choose Mesh/Make. A window appears, asking you if you want to reset the

facetter settings. As a rule, the settings are acceptable, so you should choose No.2. If you choose Yes, the Settings for Initial Surface Triangulation window

appears.3. Enter the maximum angular deviation for each type of Cone/Cylinder, Sphere,

Torus, and Spline object in the model in its respective Max angular dev fields. Bydefault, these values are set to 15 degrees. Note that you cannot change theangular deviations or surface deviations for a plane.

4. Enter the maximum surface deviation for each object type in their respective Maxsurf deviation fields. By default, these values are set to 0 mm.

5. Enter the maximum aspect ratio for each object type in their respective Maxaspect ratio fields. By default, these are set to 20, except for planes, which are setto a default of 200.

6. Choose OK to accept the settings or Cancel to ignore the settings. Optionally,choose Reset to restore the values to their defaults before continuing. A bar willappear indicating the progress of the mesh it creates. Choose Abort to stop themeshmaker from creating the mesh.

Make Creates a finite element mesh on a seeded object.Delete Deletes your mesh on an object.Mesh Info Displays information about your mesh.Show Mesh Displays the mesh over the entire object.Display Parameters Displays various aspects of the mesh.


Mesh/MakeSettings for Initial Sur-face Triangulation




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Mesh/Delete

Use this command to delete a mesh you have created. Once you have deleted a mesh,you can reseed or create a different mesh for the object.

> To delete a mesh:1. Choose Mesh/Delete. A confirmation window appears, asking you if you are sure

you want to delete the mesh.2. Choose Yes.

The mesh is deleted.

Mesh/Mesh Info

Use this command to display the numbers of total tetrahedra, the maximum and minimumvolumes, the number of the solids, and the names of the objects in the model.

> To see information about the existing mesh:1. Choose Mesh/Mesh Info. The Mesh Information window appears.2. Choose OK to return to the Meshmaker or Help for more information on the mesh.

Mesh/Show Mesh

Use this command to toggle the mesh display on and off. A check box appears next to thiscommand if the mesh is shown.

> To show the mesh on an object or face:• Choose Mesh/Show Mesh.

Choose it again to turn off the mesh. The check box will vanish.






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Mesh/Display Parameters

This command allows you to set the display parameters of the mesh.

> To display the mesh:1. Choose Mesh/Display Parameters. The Set View Parameters window appears.2. Choose More to expand the window.3. Select the Display Type of the mesh:

4. Select the Plot Mode of the mesh:

5. Enter the Scale Percentage of the mesh in the plot. This value controls how largethe tetrahedra of the mesh appear in the plot. For example, if you enter 50 as thescale percentage, the tetrahedra in the mesh will appear to be 50% smaller thanthey actually are. This is useful when you want to see the edges of the tetrahedra.

6. If you chose Show triangles, under On faces, select the mesh display on thefaces of the objects in the mode:.

7. Optionally, if you chose Show triangles, or Show tetrahedra, select On anarbitrary box to plot the mesh inside a box. This is useful when inspecting mesheson arbitrary regions.a. Toggle on Do not plot outside the box. This prevents the Meshmaker from

plotting the mesh on objects outside the region of the box.

No mesh Leaves the mesh hidden, which is useful when you want to viewthe mesh in one window and the model in another.

Show points Shows only the points of the tetrahedra in the mesh.Show triangles Shows the surface triangles of the mesh. This is the default.Show tetrahedra Displays the full tetrahedra of the finite element mesh.

Shaded plot Fills the mesh of the objects in the model with solid colors.Hiddenline plot Displays the shaded surface meshes as wireframed.Wireframe plot Shows only the outlines of the tetrahedra in the mesh.

Plot on all faces Plots the mesh on all the faces of all the objects in the model.Plot on selectedfaces

Plots the mesh on only the selected faces of objects.

Plot on unselectedfaces

Plots the mesh only on the unselected faces of objects.



Mesh/DeleteMesh/Mesh InfoMesh/Show MeshMesh/Display Parame-ters



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Mesh/DeleteMesh/Mesh InfoMesh/Show MeshMesh/Display Parame-ters

b. Choose Define/Change Box.c. Enter the coordinates of the Box base vertex in the coordinates fields.d. Choose Enter to accept the vertex point or Cancel to ignore the box.e. Enter the dimensions of the box in the Enter box size fields.f. Choose Enter to accept the box dimensions or Cancel to cancel the action.

8. Choose OK to accept your values or Cancel to cancel the command.


Maxwell 3D — Refine MenuTopics:

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Refine MenuAfter the mesh is completed, you may need to refine the mesh to obtain more accurateresults that will converge faster. The Refine menu is enabled only after a mesh is created.The commands in the refine menu allow you to:

• Refine the mesh of the face or surface of an object.• Refine the mesh of an object or box.• Define or clear the meshing region.

When you choose Refine from the menu bar, the following menu appears:

When refining the mesh on an object or face, the 3D Meshmaker selects all the tetrahedrain the problem and finds the largest length, area, or volume. After it finds the largest value,the 3D Meshmaker refines the mesh until the value of the length, area, or volume reachesthe specified value.

Refine CommandsThe following commands are available in the refine menu:

Object Face Refines the mesh on the face of an object.Object Refines the mesh for the entire object.Box Refines the mesh on a box.

Refine MenuRefine CommandsRefine/Object Face

Refine/Object Face/ByVolume

Refine/Object Face/By Tri-angle Area

Refine/Object Face/ByLength

Refine/Object Face/BySkin Depth

Refine/ObjectRefine/Object/By VolumeRefine/Object/By Length

Refine/BoxRefine/Box/By VolumeRefine/Box/By Length



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Refine/Object FaceUse these commands to refine the mesh on the selected face of an object. If an object isselected, all of its faces will be refined. Choose one of the following from the Refine/Object Face menu:

Refine/Object Face/By Volume

Choose this command to refine the volume of all the tetrahedra until they are below theentered refinement parameters.

> To refine the volume meshing on the face of an object:1. Select the face of an object to refine using the selection commands.2. Choose Refine/Object Face/By Volume. The Seed/Refine controls window



4. Select Maximum element volume to specify the maximum volume of theelements touching the selected faces. The Meshmaker refines all the elementstouching the selected faces until their volume is equal to or less than the volumeyou specify. If you select this, enter the maximum volume of the elements in theedit field on the right.

5. Choose OK to accept the refinement numbers or Cancel to cancel the action.

The Meshmaker then refines the mesh.

By Length Refines the length of all the tetrahedra until they are below the enteredValue.

By TriangleArea

Refines the area of the triangles of the tetrahedra until they are belowthe entered Value.

By Volume Refines the volume of the tetrahedra until they are below the enteredValue.

By SkinDepth

Refines the skin depth region by the calculated Skin Depth value.










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Refine/Object Face/By Triangle Area

Choose this command to refine the area of the triangles of the tetrahedra until they arebelow the entered refinement parameters.

> To refine the volume meshing on the face of an object:1. Select the face of an object to refine using the selection commands.2. Choose Refine/Object Face/By Triangle Area. The Seed/Refine controls

window appears.3. Optionally, select Maximum number of elements to be added to specify the


4. Select Maximum surface triangle area to specify the maximum area of thesurface triangles (the faces of the tetrahedra touching the surface). TheMeshmaker refines all the surface triangles until their area is equal to or less thanthe area you specify. If you select this, enter the maximum area of the triangles inthe edit field on the right.

5. Choose OK when you have finished specifying the refinement criteria.




Refine/Object Face/ByTriangle Area







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Refine/Object Face/By Length

Choose this command to refine the length of all the tetrahedra until they are below theentered refinement parameters.

> To refine the length meshing on the face of an object:1. Select the face of an object to refine using the selection commands.2. Choose Refine/Object Face/By Length. The Seed/Refine controls window















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Refine/Object Face/By Skin Depth

Unlike the By Volume, By Triangle Area, and By Length options, which allow you torefine the object by refining the characteristics of the mesh, By Skin Depth allows you torefine all the tetrahedra within a specified skin depth.

> To refine the mesh by skin depth:1. Select the faces to refine using the commands in the Edit menu.2. Choose Refine/Object Face/By Skin Depth. The following window appears:


4. Enter the number of layers perpendicular from the object’s surface to add points in


Refine/Object Face/By Vol-ume








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the Number of layers of elements field. The Meshmaker adds an equivalentnumber of points to each layer as it added on the surface. For example, if theMeshmaker added 10 points to satisfy the Surface triangle length of the trianglemesh on the surface, it will add 10 points to each layer.

5. Enter the skin depth within which to refine the mesh in the skin depth field. Youmay also calculate the skin depth using the Calculate Skin Depth command. Theresults of that calculation appear in the skin depth field.

6. Enter minimum edge length of the surface mesh in the Surface triangle length field.The Meshmaker refines the surface triangle mesh (the faces of the tetrahedratouching the surface) until their edge length is equal to or less than the edge lengthyou specify.

7. Choose Calculate Skin Depth to calculate the skin depth based on the material’spermeability and conductivity, and the frequency of the problem. The results of thiscalculation are automatically used in the skin depth field. To calculate the skindepth, do the following:a. Choose Calculate Skin Depth. A window appears prompting you for the

relevant information.b. Enter the relative permeability of the material in the Relative Permeability

field.c. Enter the conductivity of the material in the Conductivity field.d. Enter the frequency of the problem in the Frequency field. The frequency must

be entered in Hz.8. Choose OK when you have finished specifying the refinement criteria.











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Refine/ObjectUse these commands to refine the mesh of a selected object. Points will be added to boththe surface and the interior of the object. Choose one of the following from the Refine/Object menu:

Refine/Object/By Volume

Choose this command to refine the volume of the tetrahedra until it is below the enteredvalue.

> To refine the meshing of the object by volume:1. Select an object to refine using the selection commands.2. Choose Refine/Object/By Volume. The Seed/Refine controls window appears.3. Optionally, select Maximum number of elements to be added to specify the


4. Select Maximum element volume to specify the maximum volume of theelements inside the selected objects. The Meshmaker refines the elements untiltheir volume is equal to or less than the volume you specify. If you select this, enterthe maximum volume of the elements in the edit field on the right.










Refine/ObjectRefine/Object/By Vol-ume

Refine/Object/By LengthRefine/Box

Refine/Box/By VolumeRefine/Box/By Length



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Refine/Object/By Length

Choose this command to refine the length of the tetrahedra until it is below the enteredvalue.

> To refine the meshing of the object by length:1. Select an object to refine using the selection commands.2. Choose Refine/Object/By Length. The Seed/Refine controls window appears.3. Optionally, select Maximum number of elements to be added to specify the














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Refine/BoxUse these commands to refine the mesh an arbitrary box in space. This is useful for refin-ing air gaps or portions of objects. The box can cut across multiple objects. Choose oneof the following from the Refine/Box menu:

Refine/Box/By Volume

Choose this command to refine the volume of a specified 3D region of the mesh.

> To refine a box by volume:1. Choose Refine/Box/By Volume. New fields appear in the side window.2. Click on a point in the view window to define the base vertex of your box or enter

the coordinates of the point in the coordinates fields.3. Choose Enter to accept this point or choose Cancel to cancel the action. New

fields appear in the side window.4. Enter the size of the box in the Enter box size fields.5. Choose Enter to accept this point or choose Cancel to cancel the action. When

you enter the size of the box, the Seed/Refine Controls window appears,displaying information about the current tetrahedra and the volume of the mesh.

6. Enter the Maximum number of elements to be added to specify the maximumnumber of elements added. The software will not exceed this value. If you selectthis, enter the maximum number of elements in the edit field on the right.

7. Select Maximum element volume to specify the maximum volume of theelements inside the specified box. The Meshmaker refines the elements until theirvolume is equal to or less than the volume you specify. If you select this, enter themaximum volume of the elements in the edit field on the right.














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Refine/Box/By Length

Choose this command to refine the length of all the mesh elements.

> To refine a box by length:1. Choose Refine/Box/By Length. New fields appear in the side window.2. Click on a point in the view window to define the base vertex of your box or enter

the coordinates of the point in the coordinates fields.3. Choose Enter to accept this point or choose Cancel to cancel the action. New

fields appear in the side window.4. Enter the size of the box in the Enter box size fields.5. Choose Enter to accept this point or choose Cancel to cancel the action. When

you enter the size of the box, the Seed/Refine Controls window appears,displaying information about the current tetrahedra and the length of the elementsof the mesh.

6. Enter the Maximum number of elements to be added to specify the maximumnumber of elements added. The software will not exceed this value. If you selectthis, enter the maximum number of elements in the edit field on the right.

7. Select Maximum element length to specify the maximum length of the edges ofthe tetrahedra inside the box. The Meshmaker refines the edges of the tetrahedrauntil they are equal to or less than the length you specify. If you select this, enterthe maximum edge length in the edit field on the right.











Maxwell 3D — Parametric Solution OptionsTopics:

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Parametric Solution OptionsThis set of menus allows you to:

• Create, open, and save a new table of data.• Add and delete project variables to a data table.• View project variables and their values.

When you choose Setup Solution/Variables from the Executive Commands menu, thefollowing window appears:

Parametric SolutionOptions

Parametric Solution OptionsMenu Commands




Entering and Revising DataValues

Save FieldsSetup Variables Tool Bar



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Parametric Solution Options Menu CommandsThe following menus are available in the Setup Variables window.

Variables Commands

Choose these commands to add, delete, or display the project variables:

When you choose Variables from the Setup Variables menu bar, the following menuappears:

File Creates, opens, and saves data tables.Edit Cut, copies, pastes, and inserts or removes rows of data.Variables Adds, deletes, and displays variables from the table.Data Fills, sweeps, and sorts rows of data.Window Cascades or tiles your view windows.Help Accesses the online documentation.

Add Adds a project variable as a column to the parametric table.Delete Deletes the selected project variable from the parametric table.View Lists all defined project variables.

Parametric Solution OptionsParametric SolutionOptions Menu Commands








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Variables/Add

Use this command to add a project variable as a column to your data table. Only variablesthat are independent of other variables and have an active effect on the model are shownin the list.

> To add variables to your table:1. Choose Variables/Add. The Add Variables window appears.2. Choose the type of variable you wish to add. A list of variables appears.3. Scroll through the list and select the variable you wish to add to your table.4. Choose OK to add the variable to the table or choose Cancel to cancel the action.

Your variable appears in the data table. If you add a Mesh Type solution option to the vari-ables table, enter 1 in the Mesh Type column to choose the Initial Mesh or enter 2 tochoose the Current Mesh.

Variables/Delete

Use this command to delete the selected project variable from your data table. The num-ber of setups will not change. When the parametric solution is executed, the value of thatvariable in each setup is assumed to be equal to its value in the nominal problem.

> To delete a variable from your table:1. Select the variable to make it active.2. Choose Variables/Delete.

The variable is deleted from the data table.

Variables/View

Use this command to see a list of all project variables and their current values in the solu-tion. This command also displays which part of the simulator uses the variable.

> To see all the variables in the problem:1. Choose Variables/View. The View Variables window appears.2. Select the type of variable you wish to see.3. Choose OK to return to the data table.









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Data Menu

Use the Data menu to do the following:

• Fill a cell or group of cells with new values.• Create and sort rows in the data table that contain a value or series of values.

When you choose Data from the Setup Variables menu bar, the following menu appears:

Data Commands

The commands in the data menu are:

Data/Fill

Use this command to change the value stored in a table cell to a certain value, or a groupof cells to a series of values.

> To fill the values in a variable:1. Select the variables below the variable name to highlight them. You will be

assigning the same value to each highlighted box.2. Choose Data/Fill. The Fill Values window appears.3. Enter the value of val(t). This is the name of the variable, usually t.4. Enter the value of t_start. This is the starting value of the data fill.5. Enter the value of t_end. This is the ending value of the data fill.6. Choose OK to accept your values or choose Cancel to cancel the action.

Fill Changes the values stored in a cell or group of cells to a certain value.Sweep Adds new rows to the data table, filling the variable columns with a new

value. Also replaces the current table with a new set of rows.Sort Arranges rows of the table in ascending or descending order, indexed

by the values of selected variables.









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Data/Sweep

Use this command to sweep a defined variable in the data table from the values of t_startto t_end. This will give a number of t sweeps.

> To sweep a defined variable:1. Choose Data/Sweep. The Sweep Setup window appears.2. Select the variable from the list to highlight it.3. Enter the value of val(t). This is the name of the variable, usually t.4. Enter the value of t_start. This is the starting value of t.5. Enter the value of t_end. This is the ending value of t.6. Enter the number of samples in the #samples field.7. Choose Accept to accept these values.8. Choose Append to add this sweep to the table. This is the default setting and

should already be active.9. Choose OK to accept the sweep or choose Cancel to cancel the sweep.

Data/Sort

Use this command to sort the variables both across the table and in ascending ordescending order.

> To sort your variables in the data table:1. Choose Data/Sort. The Sort Setup window appears.2. Select the item from the Variables window that you want to start the table with.3. Choose Add to add the variable to the Sort Keys window. You can return this

variable to the variable column by selecting it and choosing Remove.4. Repeat steps two and three until you have arranged the variables to your

satisfaction.5. Select whether you want to arrange the setups in ascending or descending order.6. Choose OK to accept the sorting or choose Cancel to cancel the action.









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Entering and Revising Data ValuesYou can enter any value in your table by clicking on it and entering a new value in the cell,or in the field below the table.

> To replace and values in the table:1. Select the box whose value you wish to change. This value appears in the Value

field below the data table. The name of the variable appears beside this field.2. Enter the value for the cell.3. Choose Enter to press Return.

The new values replace your old ones.

Save FieldsSave Fields allows you to save the field of the parametric setup so that it may be plottedafter a solution has been generated.

> To save the field of a parametric sweep:1. Select the N from the Save Fields column of the setup you wish to plot after the

solution. The N appears in the field at the bottom of the parametric table2. Enter Y in the field.3. Choose Enter.

The Y appears in the Save Fields column. The setup can now be used to create a plot ofthe fields after a solution has been generated.

Setup Variables Tool BarBelow the menu bar, a tool bar displays a series of icons that activate different com-mands. Click on one of the icons for a description of each icon command.

Parametric Solution OptionsParametric Solution OptionsMenu Commands




Entering and RevisingData Values


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