# ansys classic

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Demonstration of ANSYS classic Part 1 (Modelling)

The text (in this format!) is an input-file to ANSYS classic, version 11.0. This input-

file is used for analyzing a clamped thick plate. The displacement and equivalent stress

(von Mises) will be plotted for the entire plate.

! Start of the input-file

! An analysis of a clamped plate

! Entering the title of the simulation/TITLE, Analysis of a clamped plate

! Entering the pre-processor! Here the material properties and the geometry will be defined,! the mesh will be created and the loads and boundary conditions will! be defined/PREP7

! Parameters, using SI-units

Youngs=210e9 ! Young's modulus [Pa]PR=0.3 ! Poissons ratio [-]DENSITY=7980 ! Density [kg/m3]a=1 ! Plate width [m]b=1 ! Plate length [m]h=0.1 ! Plate height [m]Pressure=500000 ! Applied pressure [Pa]nx=10 ! Number of elements in x-direction [-]ny=10 ! Number of elements in y-direction [-]nz=2 ! Number of elements in z-direction [-]

! Creating a 3D-plate by defining the dimensions using the command! block.

BLOCK,0,a,0,b,0,h

! The element type is a 20-node solid element, SOLID186ET,1,SOLID186

! Material properties, a normal steelMPTEMP,,,,,,,,MPTEMP,1,0MPDATA,EX,1,,YoungsMPDATA,PRXY,1,,PR

! Defining number of elements per line, used for meshingLESIZE,2,,,nx,1,4,0,0,0LESIZE,7,,,nx,1,4,0,0,0LESIZE,4,,,nx,1,4,0,0,0

LESIZE,5,,,nx,1,4,0,0,0LESIZE,1,,,ny,1,4,0,0,0LESIZE,3,,,ny,1,4,0,0,0LESIZE,6,,,ny,1,4,0,0,0LESIZE,8,,,ny,1,4,0,0,0LESIZE,9,,,nz,1,4,0,0,0LESIZE,10,,,nz,1,4,0,0,0LESIZE,11,,,nz,1,4,0,0,0LESIZE,12,,,nz,1,4,0,0,0

! Meshing the plate, using sweep...

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VSWEEP,ALL

! Locking all the sides, making the plate clampedDA,3,All,0DA,4,All,0DA,5,All,0DA,6,All,0

! Applying pressure on top of the plateSFA,2,1,PRES,Pressure

! Exits the pre-processor and enters the solution processorFINISH/SOLU

! Defining the type of analysis, in this case a static one.! SOLVE= Solving the problem...ANTYPE,0SOLVE

! Exits the solution processor and enters the post-processorFINISH/POST1

! Saves the database information, in order to analyze it in the nextpart! Stores all the data availableSAVE,Demo,DB,,ALL

! End of the input-file

Tip! In the help file, a description of every command and its location (how you reach itfrom the GUI, by clicking in the menus) can be found. The help file is found at Help-

>Help topics.

Tip! In the Session Editor, every command that has been used in the simulation is

logged.

Performing an analysis with ANSYS can be done in several ways; this is a recall of the

steps taken in this simulation.

1. Preferences, selecting the type of simulation.2. Preprocessor, entering the preprocessor where the model is created, meshed and

loads and boundary conditions are applied.

3. Element Type, defining which type of elements to use (in the simulation aboveSOLID186).

4. Material Props, defining the material properties.5. Modeling, creating the geometry used in the simulations.6. Meshing, defining the mesh for the plate.7. Loads, defining the type of analysis, the loads and the boundary values for the plate.8. Solution, here the problem is solved; the loads can be defined here as well.9. Solve, used for solving the problem.10.General Postproc (or TimeHist Postproc), here the results are post processed (this

part will be discussed in the next half).

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Demonstration of ANSYS Part 2 (Post processing)

Here, the plate analyzed in part 1 will be post processed. The equivalent von Mises stress

and displacement inz-direction will be processed in different ways.

The following things will be generated:

1. A plot showing the equivalent von Mises stress distribution in the plate and thedisplacement in thez-direction.

2. A path will be generated, a plot showing how various results changes as functionof a geometrical parameter, plate width or thickness for example. The values of

the path will be stored as well.

3. The displacement for three nodes in the middle of the plate will be stored.4. The stress matrix for each node in model.

! Start of input file

! Input file used for post-processing the results from a simulation

! Opening the input-file, resuming the file (opens the database file)RESUME,Demo,DB,,0,1

! Entering the post-processor/POST1

! Plotting the equivalent stress (von Mises)! Creating an image of the stress, called vonMises.pngPLNSOL,S,EQV/VIEW,1,1,1,1/IMAGE,SAVE,vonMises,png,

! Plotting the displacement in the z-direction! Creating an image of the displacement, called Displacement.pngPLNSOL,U,Z/VIEW,1,1,1,1/IMAGE,SAVE,Displacement,png,

! Defining the pathPATH,Demo_path,11,30,20PPATH,1,,0*a,0.5*b,h,1PPATH,2,,0.1*a,0.5*b,h,1PPATH,3,,0.2*a,0.5*b,h,1PPATH,4,,0.3*a,0.5*b,h,1PPATH,5,,0.4*a,0.5*b,h,1PPATH,6,,0.5*a,0.5*b,h,1PPATH,7,,0.6*a,0.5*b,h,1

PPATH,8,,0.7*a,0.5*b,h,1PPATH,9,,0.8*a,0.5*b,h,1PPATH,10,,0.9*a,0.5*b,h,1PPATH,11,,1.0*a,0.5*b,h,1

! Mapping items to the pathPDEF, ,U,Z,AVG ! Displacement in z-directionPDEF, ,S,EQV,AVG ! Equivalent von Mises stress

! Plotting the path

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PLPATH,UZ/IMAGE,SAVE,Displacement_path,png

PLPATH,SEQV/IMAGE,SAVE,Von_Mises_path,png

! Command used for storing values from the mid-nodes/EFACET,4

! Storing the items generated from the path, displacement andequivalent stress! The command page governs the page properties./PAGE,4000,80,4000,80/OUTPUT,Path_information,txt,,APPENDPRPATH,UZ,SEQV/OUTPUT

! Storing the displacement and stress vector in the node situated inthe middle of the plate...Mid1 = node(0.5*a,0.5*b,0)Mid2 = node(0.5*a,0.5*b,0.5*h)Mid3 = node(0.5*a,0.5*b,h)

*GET,U1,NODE,Mid1,U,Z*GET,U2,NODE,Mid2,U,Z*GET,U3,NODE,Mid3,U,Z

! (F15.10) is Fortran number format.../output,Mid_displacements,txt,,append/COM, Displacements for mid-nodes in z-direction*VWRITE,U1, U2, U3, , , , , , ,(F15.10)

/output

! Storing the stress matrix for all nodes/OUTPUT,Stress_matrix2,txt,,APPENDPRNSOL,S

/OUTPUT

! End of input file/eof

Tip! When using the command /COM, the comment is written in the output window,

which is not the case when using !

The post processing in ANSYS can be done in several ways, depending on which results

that are desired. Two different post processors are available in ANSYS (GeneralPostproc andTimeHist Postproc), here the general postprocessor will be described. The

time historic postprocessor processes results from a transient analysis, i.e. an analysis

with time as a variable. The following items are used in this analysis:

o List results, used for listing results for example the stress state in each element.o Results viewer, used for visualizing the results, e.g. the maximal principal stress.o Path operations, used for visualizing how the displacement changes over the

width of the plate.