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POINTWISE

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POINTWISE

OUTLINE

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• Introduction

– Installation

– Advantages

• Pointwise Terminology

• Examples

– Flow over a sphere

– Shoulder mesh for blunt bodies

• Tips and Tricks

INSTALLATION

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1. Go to the download page at:

www.pointwise.com

2. Follow installation instructions found on the same

download page

3. Specify license server:

shyylab.engin.umich.edu

Limited number of licenses (2 for both labs)

ADVANTAGES

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• Better grid quality due to a mixture of automated mesh

generation and flexible manual controls

• Easier learning curve than Gambit

• Better product support

• Industry standard

Pointwise Gambit

POINTWISE TERMINOLOGY

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Database – CAD geometry imported from other sources

or created directly within Pointwise (used to control the

shape of grid elements, but not necessary for mesh

creation)

Connector – a 1D grid element which forms the

foundation for all other grid hierarchy

Domain – a 2D grid element which can be structured or

unstructured

Block – a 3D grid element which can be structured,

unstructured or hybrid

Dimension – number of grid points assigned to a

connector

EXAMPLE 1

FLOW OVER A SPHERE

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• Generate viscous grid for hypersonic flow over a sphere

(axisymmetric)

• Start with a Gambit grid (i.e. geometry)

• Example will cover:

– Importing geometry created in Gambit to Pointwise

– Generating a hexahedra grid in Pointwise (automatic

and manual options)

– Exporting a LeMANS-compatible mesh file

1. Export IGES (geometry) file in Gambit:

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2. Import DATABASE (IGES file) in Pointwise:

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3. Modify DATABASE

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4. Create CONNECTORS

2-point connectors

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5. Dimension CONNECTORS

Number of points

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6. Distribute points along CONNECTORS

(a) Grid->Distribute

(b) Cluster points towards the wall

(c) Distance of 1st point from wall

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7. Assemble DOMAIN

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8. Modify DOMAIN grid using the solver

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9. Examine mesh quality (based on skewness equiangle)

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10. Set solver, boundary conditions and volume conditionsSolver: CAE -> Select Solver… -> ANSYS FLUENT

Boundary Conditions: CAE -> Set Boundary Conditions… -> New

Volume Conditions: CAE -> Set Volume Conditions… -> Check and select FLUID

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11. Export FLUENT CASE file (not compatible with LeMANS)

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12. Import CASE file in Gambit and export MESH file

(temporary)

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EXAMPLE 2

SHOULDER MESH FOR BLUNT BODIES

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• Manipulate Pointwise Solver options to improve grid

quality over MSL shoulder

• Edge attributes in solver allow the user to adjust the

spacing and angle between the boundary grid points and

the first layer of grid points inward from the boundary

1. Assemble Domain:

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2. Modify Solver “Edge Attributes”:

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Spacing: InterpolateAngle: Interpolate

Spacing: Current GridAngle: Current Grid

Spacing: Current GridAngle: Orthogonal

EXAMPLE 2

RESULTS

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With SolverWithout Solver

TIPS & TRICKS

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• Elliptic solver floating boundaries –

produce domain interfaces with nice

orthogonality and distribution

• Examine rules – specify a set of “rules” to let Pointwise

alert you when certain grid quality criteria you set are no

longer met

• Bezier curves – give more control (control slope) and are

ideal for specifying farfield boundary curves that need to

be orthogonal to axis of symmetry

• Additional documentation can be found in your Pointwise

directory (i.e. /Pointwise/PointwiseVxxxx/doc)