Project 2

Preprocessing Rear Suspension Assembly using ANSA.

Aim:

• For the given assembly check for the geometrical errors and mesh with given element quality criteria.
• Assemble the components by deploying necessary connections.

Methodology:

• Geometry cleanup
• Mid surface generation for parts with uniform thickness less than 5 mm.
• Generate 2D mesh for the mid surface by satisfying below mentioned quality criteria.

S. No	Quality Criteria	Value
1	Target Length	4
2	Minimum Length	2
3	Maximum Length	6
4	Aspect Ratio	3
5	Skewness	45
6	Warpage	15
7	Jacobian	0.7
8	Min. Quad Angle	45
9	Max. Quad Angle	135
10	Min. Tria Angle	30
11	Max. Tria Angle	120
12	Tria percentage	15

• Generate 3D mesh for tyre and rim by satisfying below mentioned quality criteria

S. No	Quality Criteria	Value
1	Target Length	6.5
2	Minimum Length	5
3	Maximum Length	10
4	Skewness	45
5	Tet-collapse	0.2

• Generate 3D mesh for remaining components by satisfying below mentioned quality criteria

S. No	Quality Criteria	Value
1	Target Length	4
2	Minimum Length	2
3	Maximum Length	6
4	Skewness	45
5	Tet-collapse	0.2

• Assemble the parts of rear suspension assembly by deploying necessary connections.

Procedure:

• The model provided for the project is rear suspension assembly of vehicle.
• The given model is opened into ANSA is as shown in fig.1.

Fig.1.Rear suspension assembly.

Geometry cleanup:

• The given model is checked for geometrical errors using checks manager.
• The errors displayed is cleared using auto fix and tools from hot points, cons, faces & surfaces.

Fig.2. Rear suspension assembly before topo cleanup.

Fig.3. Rear suspension assembly After topo cleanup.

Midsurface Extraction:

• The mid surface is extracted for parts having uniform thickness less than 5 mm.
• The mid surface of the parts is extracted using tool faces>offset option.

Fig.4. Mid surface of parts with uniform thickness.

Assigning shell property and thickness:

• The mid surface is assigned with new PIDs is as shown in fig.5.

Fig.5. Mid surface assigned with PIDs.

2D Meshing:

• The quality criteria & mesh parameters values are entered.
• The perimeter length value assigned is 4 mm.
• Using spot mesh option each macro area is selected and meshed.
• The quality criteria are achieved by using tools like cut, join, past, Num +/-, reconstruct, smooth, split and swap options.
• The tria percentage is reduced by deleting unwanted construction lines without losing the feature.
• The smooth mesh flow is achieved by creating small macro areas and restructuring the mesh.
• The shell to solid feature is enabled to ensure the feature capturing is matching with parent geometry.
• The meshed model is as shown in the fig.6.

Fig.6. 2D Mesh generated on mid surfaces.

3D Meshing of Tyre and Rim:

• The quality criteria & mesh parameters values are entered.
• The perimeter length value assigned is 6.5 mm.
• Using spot mesh option each macro area is selected and meshed.
• The quality criteria are achieved by using tools like cut, join, past, Num +/-, reconstruct, smooth, split and swap options.
• The 3D mesh is generated using Tetra Rapid method.

Fig.7. 3D Mesh generated on Tyre and Rim.

3D Meshing of remaining components:

• The quality criteria & mesh parameters values are entered.
• The perimeter length value assigned is 4 mm.
• Using spot mesh option each macro area is selected and meshed.
• The quality criteria are achieved by using tools like cut, join, past, Num +/-, reconstruct, smooth, split and swap options.
• The 3D mesh is generated using Tetra Rapid method.

Fig.8. 3D Mesh generated on Remaining components.

Fig.9. Rear suspension assembly meshed.

Deploying necessary connections:

• The components are assembled using necessary connections such as cluster RBE2 for rigid connections and 2 nodes RBE2 for bolted connections.
• The spring is modelled using CBAR element to deploy connection.
• The rear suspension assembly with connections is as shown in fig.10.

Fig.10. Rear suspension assembly meshed and connected.

Learning Outcomes:

• Mastered the usage of various tools of ANSA software.
• Able to fix the geometrical errors for given complex model.
• Able to extract mid surface for the given model.
• Mastered various meshing techniques.
• Mastered to deploy necessary connections.

Conclusion:

• The given model is imported to the ANSA software and the geometrical errors are fixed.
• The mid surface is generated and meshed for parts with uniform thickness less than 5 mm.
• The remaining parts are meshed using 3D mesh.
• The parts are assembled using necessary connections.

Google Drive Link:https://drive.google.com/file/d/1oLiRXnIX3dCjtVCw6aoJz1rU7NurbOa0/view?usp=sharing