Week- 5 - Solid meshing
AIM:
- To mesh the given rear view mirror component in both 2D and 3D after checking the model for geomentrical errors and fixing them.
- Also,ensure the generated mesh flows the given quality criteria.
Quality criteria:
Shell element
|
S.No |
Quality Criteria |
Value |
|
1 |
Target/Average length |
1 |
|
2 |
Minimum Length |
0.5 |
|
3 |
Maximum Length |
2 |
Solid elements
Only one requirement:Tet collapse should be a maximum of
|
S.No |
Quality Criteria |
Value |
|
1 |
Tet collapse |
0.2 |
for solid elements.
CAD MODEL IMAGE:

Procedure:
- Firstly ,we need to use the topo tool to take care of all the single cons and to ensure there are no free edges .
- It can be accessed via FACES>TOPO in the topo module.
- All the cons are selected and the algorithm takes care of all the single cons.


- After that, as is the norm with meshing on ANSA and before we carry out any other actions, we need to carry out a geometry check and fix all abnormalities.
- That is done via Checks > Geometry where we can execute checks of certain defects that can be selected from the menu and the algorithm looks for said defects.
- After detection, we can select all the defects and right-click > fix to fix them.


- After orienting the model, using the Faces > Orient tool, we can go ahead and work on meshing the surface of the model.
- As part of this, we need to assign the mesh properties and quality parameters.
- We need to assign the target length.
- To do this, we can go to the mesh module and Perimeters > Length.
- This lets us adjust the target length and effectively, the resolution of the cons to be finer. As is required, the length would be 1mm.

- After that, we can assign the parameters.
- This is done by accessing mesh parameters and quality criteria from the top toolbar and then we can input the given values

- In the case of quality criteria, we will need to access the solids tab as well to input the tet collapse criteria.


- Since some regions might fail for minimum tool, they can be modified by taking care of the boundaries (cons).
- The cut tool can be used to suppress some of these cons and in other regions, we can create cuts.
- All this to ensure the mesh generated would be favourable and does not fail for any of the criteria.


- Now we can go ahead and mesh the component. The spot mesh tool is used (Mesh Generation > Best). For regions that are flat and not as complicated, the tria mesh can be used.

- In the more complex regions (such as fillets and hemmings), we can make use of the ortho tria tool.



- After each mesh iteration, we will need to reconstruct the mesh using Shell Mesh > Reconstruction.
- For this to be effective, the neighbouring mesh is selected as well.
- This ensures the reconstructed mesh is of good quality and flow.


- After meshing all regions (and ensuring there are no off elements - should be taken care of already through reconstruction), we can proceed to the next step of assigning volumes manually to each set of closed-shell elements.
- This is done by using Volumes > Define > Manual and then selecting the regions that comprise a particular volume.
- In this case, the PID selection tool from the bottom left toolbar would be useful in selecting the entire volume since the property ID has already been assigned for certain regions.

- After selection, it's just a matter of middle-clicking for the software to recognize the volume. All the volumes are identified this way.

FINAL MODEL IMAGE:

3D VOLUME MESH ELEMANTS

LEARNING OUTCOMES:
- Learnt some tools related to solid meshing.
- Learnt to assign volumes for closed shell element regions.
- Learnt to fix tet collapse failures.
- Familiarized with the ortho tria and tria mesh types through the spot mesh tool.
RESULT:
- The given component was geometrically fixed and meshed as per the given requirements and criteria and the generated shell mesh was used to create the solid mesh.
- Quality and flow were achieved and care was taken to ensure there were no deformations of any kind on the surface.