Week 8-Challenge

Week 8 Challenge: Generating 3D mesh on the given components

OBJECTIVE: To generate 3D Tetramesh on the given models by following the given quality parameters.

PROCEDURE:

Quality Parameters :

Target Element Length (Housing Model) = 5mm 

Target Element Length (Model 2 & Model 3) = 6mm 

Min Length - 2mm, Max Length - 7mm 

Tet collapse: 0.15

1. HOUSING MODEL:

Import the geometry into HyperWorks.

Perform Geometry Cleanup on the model using the geometry cleanup panel (F11). Change the 'Geometry Color Mode' to ‘By Topo’ and look for free edges and rectify if any free edges are found.

Multiple methods are available to perform 3D tetramesh,

1. 2D Tria elements are first generated on the surface of the component. Then from the 2D shell elements the 3D Tetramesh is generated. This method is preferred in the industry.
2. Direct Tetramesh of the components using the option available under the 3D Tetramesh menu.
3. Using ‘Quick Tetramesh’ option available under the ‘Utility’ Browser.
4. Using ‘Volume Tetramesh’ option available under 3D Tetramesh menu.

Since there are 2 components, all the processes are carried out on one component after the other.

    i) Hub Component:

For the Hub component, the ‘Quick Tetramesh’ option available under the 'Utility' Browser is used. 

(View > Browsers > HyperMesh > Utility > Geom/Mesh > Quick TetraMesh > Mesh Size = 5)

Mask some elements to see the interior of the component, to ensure that 3D Tetramesh has been carried out properly.

After meshing, the ‘tet collapse’ of the Tetra elements need to be checked. (F10 > 3d > tet collapse)

Ensure that there are zero elements failing the ‘Tet collapse’ value. If any elements are found failing the given ‘tet collapse’ value then ‘Tetra remesh’ is carried out after changing the quality parameters under the ‘Tetramesh Parameters’ menu.

    ii) Cover Component:

Perform Geometry Cleanup on the component.

For the Cover component also, ‘Quick Tetramesh’ method is used. 

(View > Browsers > HyperMesh > Utility > Geom/Mesh > Quick TetraMesh > Mesh Size = 5)

2. MODEL 2:

Import the geometry into HyperWorks.

Perform Geometry Cleanup on the model using the geometry cleanup panel (F11). Change the Geometry Color Mode to ‘By Topo’ and look for free edges and rectify if any free edges are found.

For the Model 2 component, ‘Volume Tetramesh’ is used. 

(3D > tetramesh > Volume Tetra > surfs > 2D type=trias > 3D type=tetras > element size=6)

Mask some elements to see the interior of the component, to ensure that 3D Tetramesh has been carried out properly.

After meshing, the ‘tet collapse’ of the Tetra elements need to be checked. (F10 > 3d > tet collapse)

Ensure that there are zero elements failing the ‘Tet collapse’ value. If any elements are found failing the given ‘tet collapse’ value then ‘Tetra remesh’ is carried out after changing the quality parameters under the ‘Tetramesh Parameters’ menu.

3. MODEL 3:

Import the geometry into HyperWorks.

Since there are 4 components, all the processes are carried out on one component after the other.

    i) Component 1:

Perform Geometry Cleanup on the model using the geometry cleanup panel (F11). Change the Geometry Color Mode to ‘By Topo’ and look for free edges and rectify if any free edges are found.

For Component  1, a 2D mesh of Tria elements is generated using the automesh option.(F12 > surfs > elem size=6)

From the 2D tria elements the 3D tetra elements are generated using the tetramesh option. 

Mask some elements to see the interior of the component, to ensure that 3D Tetramesh has been carried out properly.

After meshing, the ‘tet collapse’ of the Tetra elements need to be checked. (F10 > 3d > tet collapse)

Ensure that there are zero elements failing the ‘Tet collapse’ value. If any elements are found failing the given ‘tet collapse’ value then ‘Tetra remesh’ is carried out after changing the quality parameters under the ‘Tetramesh Parameters’ menu.

For the rest of the Model 3 components, ‘Volume Tetramesh’ is used. 

(3D > tetramesh > Volume Tetra > surfs > 2D type=trias > 3D type=tetras > element size=6),

    ii) Component 2:

Geometry Cleanup,

Volume Tetramesh,

Checking the tet collapse of 3D Tetra elements,

    iii) Component 3:

Geometry Cleanup,

Masking some elements to check whether 3D Tetramesh has been carried out properly,

Checking the tet collapse of 3D Tetra elements,

    iv) Component 4:

Geometry Cleanup,

Masking some elements to check whether 3D Tetramesh has been carried out properly,

Checking the tet collapse of 3D Tetra elements,

Final Model 3 Image:

CONCLUSION:

The given models were meshed according to the given quality parameters. By doing so was able to gain experience in performing Geometry Cleanup and generating 3D Tetramesh on components of various complexity.