Week 8-3D Tetra Meshing Challenge
1.OBJECTIVE
Create a Teramesh for Housing component with the given quality criteria by 2D to 3D Conversion and check for no element failure.
PROCEDURE
Import the "housing.stp" file using the import tool option.
Using the Geometry menu in the menu bar, use the geometry cleanup tools to ensure a fully enclosed volume. Check the topology and verify if we still have free edges.
MODEL TOPO:
3D-MESH:
Click on automesh panel from the 2-d elements page. Select the surfaces and put element type as trias. We will set the target element length as 5 units. Minimum length as 2 units and maximum length as 7 units
After meshing the surfaces and ensuring that no elements are failing for minimum and maximum element length, we can proceed to convert the 2-d tria elements to 3-d tetra elements.
Access the Tetramesh panel from 3D page, and then click on tetramesh subpanel.
Select the elements selector under Fixed trias/quads to tetra mesh. Click mesh to generate the tetrahedral elements.
Use Check Elements panel and go to the 3-d subpanel. Identify elements having a tet collapse value smaller than 0.15.
Remesh the hub’s displayed tetra elements to improve their tetra collapse. Under tetramesh parameters check the minimum tetra and maximum tetra element length box. Also, check the fill voids, fill midnodes and smoothing box. Set the tet collapse value as 0.15.
Another method to improve the tet collapse is by using distance option. The elements that failed the tetra collapse check is saved in the user mark by clicking on save failed, and can be retrieved in mask panel using the extended selection menu.
We can increase the distance to improve the tet collapse value.
CONCLUSION
Performed tetrahedral mesh generation by converting the 2D elements into 3D.Achieved a better mesh by clearing the 3D mesh quality errors.
2.OBJECTIVE
Use the quick tetra mesh to mesh the geometry and Review the quality of the tetra mesh to avoid failure and tet collapse.
PROCEDURE
Import the model file using the import tool option.
Observe the topology of the geometry by using the visualisation option. Make sure that there are no free edges i,e no red lines inside the geometry or any missing surfaces.
We can access the Quick tetra menu under View >Browsers >Hypermesh > utility. Go to Geom/Mesh and select quick tetraMesh under Mesh tools.
Select the component and put trias only as mesh type. Fill mesh size as 3 units. Click the mesh button to mesh the component.Select element type as Trias only.
Use Check Elements panel and go to the 3-d subpanel. Identify elements having a tet collapse value smaller than 0.150.
Remesh the model displayed tetra elements to improve their tetra collapse. Under tetramesh parameters check the minimum tetra and maximum tetra element length box. Also, check the fill voids, fill midnodes and smoothing box. Set the tet collapse value as 0.150.
We could also improve the tet collapse is by using distance option or press F4 on the keyboard. The element that failed the tetra collapse check is saved in the user mark by clicking on save failed, and can be retrieved in mask panel using the extended selection menu and when selected click on reverse.
We can increase the distance to improve the tet collapse value .
CONCLUSION
The 3-D mesh is generated using the quick tetra method.Performed 3-D quality check and removed all the elements failing for tet collapse.
3. OBJECTIVE
To Mesh the components using volume tetra meshing technique or Quick tetra mesh .Perform elements quality check on each of the components.
PROCEDURE
Import the Model file from the import model tool.Take a moment to inspect the geometry. For the model component we will convert the trias elements into tetras elements.
In order to mesh the model with tria's we need to perform topology cleanup.remove the solids from all the component. Remove the surfaces where elements will fail for minimum length. Defeature all of the small surface fillets. Use toggling and replacing points options to clean the geometry from Quick edit panel in Geom.
Mesh the components with trias and mesh size as 3 and then generate the tetrahedral elements using tetra mesh panel.
Follow the same for rest of the components in the model and check for topological errors
Go to the Check Elements panel to eliminate the failing elements. Identify elements having a tet collapse value smaller than 0.150.
Select Save failed for failed elements and in mas option select elems->retrieve-> mask-> reverse.
We can correct the failing elements by remeshing with tetramesh parameters. Increasing the distance between nodes using distance tool can also fix the failing elements.press F4 and adjust the distance between the nodes.
CONCLUSION
Tetrahedral mesh generated using the and quick tetra mesh and 2D-3D conversion.Remeshed with tetra parameters to achieve a better element quality.