Week 4 Challenge : CFD Meshing for BMW car

Aim/Objective: Solve all geometrical errors on half portion and Assign appropriate PIDs. Perform meshing with the given Target length and element Quality criteria. After meshing the half model, Do symmetry to the other side.

Procedure: 

1. Import the model to ANSA.
2. if model is symmetrical. delete one part of symmetry model.
3. switch to the TOPO module.
4. check and solve the errors part by part.
5. Run the geometry check. solve the single cons and triple cons.
6. use the curves to recreate the surfaces where we cannot get cons to create surface.
7. Close the volumes. we had 7 volumes in this model. (1 body , 4 wheel, 2 silencer )
8. Create PID with respect to different component. Check the model thoroughly for overlapped surfaces and single and triple cons. 
9. Switch to Surface mesh.
10. Define target length and type in mesh parameter and quality criteria with respect to the components.
11. Define the length perimeters and macros
12. At last we need to create the mesh for the body so that mesh will be proper at the different mesh length.
13. Mesh the model one PID by one PID by spot mesh.
14. we need to check off elements by swithching the model to hidden mode.
15. if the element are not meeting the quality criteria. it will show the error with respected the color.
16. reconstruct the surface to reduce the off elements to zero. 
17. use the smooth to solve the off elements.
18. if smooth and reconstruct option is not working. We need to  solve manually by using options like split, move and paste.
19. save frequently to save work if Ansa crashing.
20. check the unmeshed the surfaces. if the target length is diferent against neighbour surface, surface wont be formed. we need to give the target length in the range to the those surfaces.
21. use the transform copy option, select the entities to symmetry. select the three points. then ok.
22. measure the length of the model. create points and curve using the Car length for Tunnel.
23. Create the base surface for the Tunnel.
24. offset the faces. close the tunnel by usning new surface with coons option.
25. Create the PID for front, rear , side top and base surface.
26. move to surface mesh module. create the spacing on the cons of all the side faces of tunnel. 
27. Mesh the top surface with 100mm length and bottom surface with 20 mm.
28. After the surface mesh, move to volumetric mesh module.
29. define the volumes and detect on whole data base. then ok.
30. we will get list of the volumes detected by Ansa. Delete the unnessarry volumes. 
31. select the required volumes. Click the remesh. Select the type Tetra CFD. Mesh the selected volumes.
32. Volumetric Mesh will be completed. Check the model thoroughly.

Learning Outcomes:

1. use of paste option for two single cons.
2. use pf undelete option properly.
3. to create points and curves. 
4. use of split the element. paste the element, move the elements.
5. Reconstruct and smoothe surface element to clear the off element. 
6. use of spacing to get proper mesh for different length.
7. copy and symmetry using three points.

Result & Conclusion:

Mesh the model with respect to Target length to the each components sucessfuly. copy the Symmetry to other side and attached the model to this report