WS10-1PAT301, Workshop 10, December 2005Copyright© 2005 MSC.Software Corporation

WORKSHOP 10Tetmeshing Anchor Geometry and

Verifying Mesh Quality

WS10-2PAT301, Workshop 10, December 2005Copyright© 2005 MSC.Software Corporation

WS10-3PAT301, Workshop 10, December 2005Copyright© 2005 MSC.Software Corporation

Workshop ObjectivesCreate a tet mesh using the auto tet mesher, TetMesh. See the effect of two TetMesh parameters on the mesher by re-meshing and changing the value of the parameters. For both meshes determine the quality of the tet elements.

Problem DescriptionTet mesh using TetMesh with the approximate element size of 20.0 or 0.5Determine the quality of the tet elements

Software VersionMSC.Patran 2005r2

WS10-4PAT301, Workshop 10, December 2005Copyright© 2005 MSC.Software Corporation

Key Concepts and Steps:Database: open an existing databaseElements: create a tet mesh using the element size of 20.0Elements: look for free element facesElements: determine the quality of the tet elementsElements: create a tet mesh using the element size of 0.5Elements: determine the quality of the tet elements

WS10-5PAT301, Workshop 10, December 2005Copyright© 2005 MSC.Software Corporation

Step 1: Open Database

Open existing database Anchor.db

a. File/Open.b. Select Anchor.db.c. Click OK.

a

b

c

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Step 2: Tet Mesh Geometric Solid

Mesh the solid.a. Elements: Create / Mesh/

Solid.b. Select Tet for Elem

Shape.c. Select TetMesh for

Mesher.d. Select Tet10 for

Topology.e. Use default values for

TetMesh Parameters…f. Select Solid 1 for Input

List.g. Enter 20.0 for Value of

the Global Edge Length.h. Click Apply.i. Click Smooth Shaded

icon.

a

bcde

g

f

h

i

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Step 3: Verify Boundaries

Look at the free faces of the tetelements.

a. Elements: Verify / Element / Boundaries.

b. Select Free Faces for Display Type.

c. Click Apply.

a

b

c

WS10-8PAT301, Workshop 10, December 2005Copyright© 2005 MSC.Software Corporation

Step 4: Determine Element Quality Using All Tests

Determine the quality of each tet element.a. Element: Verify / Tet / All.b. Click Apply.c. See spread sheet on next page,

Continued…

a

b

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Step 4: Determine Element Quality Using All Tests (Cont.)

Results of quality checks.a. Test performedb. Number of elements that failed

test

Results of quality checks.c. Poorest quality check resultd. Element that had poorest

quality check result

a b c d

WS10-10PAT301, Workshop 10, December 2005Copyright© 2005 MSC.Software Corporation

Step 5: Element Aspect Ratio Using Fringe Plot

Create a color fringe plot for the tetelement aspect ratio..

a. Element: Verify / Tet / Aspect.

b. Adjust Aspect Ratio to a value near 5.

c. Click Apply to obtain the fringe plot of aspect ratio.

d. Click View Corner icon and drag to show close-up view.

a

b

c

d

d

WS10-11PAT301, Workshop 10, December 2005Copyright© 2005 MSC.Software Corporation

Step 6: Re-Tet Mesh Geometric Solid

Re-mesh the solid to try to create animproved mesh.

a. Elements: Create / Mesh / Solid.

b. Select Tet for Elem Shape.c. Select TetMesh for Mesher.d. Select Tet10 for Topology.e. Click TetMesh Parameters…f. Enter 0.05 for Maximum h/L.g. Enter 0.1 for Global Edge

Length multiplier.h. Click OK.i. Select Solid 1 for Input List.j. Enter 20.0 for Value.k. Click Apply.l. Click Yes for delete the existing

mesh on Solid 1.

a

bcd

e

g

f

h

i

j

k

WS10-12PAT301, Workshop 10, December 2005Copyright© 2005 MSC.Software Corporation

Step 7: Element Quality Using All Tests for New Mesh

Original Mesh Re-Mesh

The tables above illustrate the differences between the first mesh and the re-mesh. Observe the large improvements made in each of the characteristics of the model after the remesh.

WS10-13PAT301, Workshop 10, December 2005Copyright© 2005 MSC.Software Corporation

Step 8: Quit MSC.Patran

Quit MSC.Patrana. Select File on the Menu Bar

and select Quit from the drop down menu

a

WS10-14PAT301, Workshop 10, December 2005Copyright© 2005 MSC.Software Corporation