Project - 2 - Meshing on the suspension Assembly
PROJECT - 2 Meshing on the suspension Assembly
AIM : To perform meshing operation following the given quality criteria and to create appropriate connections to the parts of the assembly .
Quality criteria :
Quality criteria for Surface Meshing of Non Uniform thickness components other than Tyre and Rim (Element type: Tria) :
|
S.No |
Quality Criteria |
Value |
|
1 |
Target/Average length |
4 |
|
2 |
Minimum Length |
2 |
|
3 |
Maximum Length |
6 |
|
4 |
Skewness |
45 |
Quality criteria for Mid surfacing of Uniform thickness part which has thickness less than 5 mm (Element type: Mixed elements) :
|
S.No |
Quality Criteria |
Value |
|
1 |
Target/Average length |
4 |
|
2 |
Minimum Length |
2 |
|
3 |
Maximum Length |
6 |
|
4 |
Aspect |
3 |
|
5 |
Warpage |
15 |
|
6 |
Skewness |
45 |
|
7 |
Jacobian |
0.7 |
|
8 |
Minimum Quad Angle |
45 |
|
9 |
Maximum Quad Angle |
135 |
|
10 |
Minimum Tria Angle |
30 |
|
11 |
Maximum Tria Angle |
120 |
Quality Criteria for Volume meshing of all Non Uniform thickness components (Element type: Tetra Elements):
|
S.No |
Quality Criteria |
Value |
|
1 |
Tet-collapse |
0.2 |
Quality Criteria for Surface Meshing of Tyre and Rim (Element type: Tria) :
|
S.No |
Quality Criteria |
Value |
|
1 |
Target/Average length |
6.5 |
|
2 |
Minimum Length |
5 |
|
3 |
Maximum Length |
10 |
|
4 |
Skewness |
45 |
PROCEDURE :
- Import the CAD geometry .
- Set the Perimeter elemental length to 1mm for getting better cons resolution using LENGTH > PEREMETER > TOPO module .
- Check the geometry for any geometrical or topological errors which can occur while transforming the CAD .
- These geometrical errors does not capture the features of the CAD properly .
- All the parts of the assembly must be set to unique PID using SET PID > FACES >TOPO module .
- Extract the Mid surface for the parts having uniform thickness or thickness less than 5mm . SKIN > MID SURFACE > FACES > TOPO or OFFSET > FACES options can be used for generating the mid surface .
- After generating the mid surface , meshing need to be done using SPOT MESH > MESH GENERATION > SHELL module .
- Create a circular zone around the hole features using ZONE CUT > FACES > TOPO . These zones act as washer elements while applying connections .
- All the parts whose thickness is more than 5mm or undefined thickness can be considered as a volume part and perform volume mesh on it .
- For creating a Volume mesh , first a surface mesh has to be created , using DEFINE > VOLUME > VOLUME MESH module the volume has to be define , using TETRA FEM / TETRA RAPID > UNSTRUCTURED MESH > VOLUME MESH module .
- Circular and curved shape faces to be captured with ORTHO TRIA elements and the flat surfaces can be captured with TRIA elements as the computational time for the ortho tria element is very high than the normal tria element .As the curved and circular faces cannot be captured properly with normal tria element , we need to use ortho tria element .
- The spring has to be captured with HEXA element , but the time taking for this method is very huge , we can capture the part with 1D element.
- To create this , a curve passing through the middle of the part is to be taken and then converted to 1D element using CBAR > ELEMENT > NASTRAN module .
- After completing the meshing process the parts need to be connected .
- In this model we use Bolt and Seam weld connection .
- After completing modelling of the assembly , using COPY > TRANSFORM option assembly can be mirrored for getting another half portion of the assembly .
LEARNING OUTCOMES:
- Leant how to capture spring with 1D element .
- Got good practise of various bolt connections .
CONCLUSION :
The given suspension assembly have been modelled with respective FE and given suitable connections where ever required .
https://drive.google.com/file/d/1ReTNZDEK3pZiJsPX7e5LW6XT-SBSlIAq/view?usp=share_link