Week 4 Challenge : CFD Meshing for BMW car

Objective: To clean up the geometrical errors of the given model and perform the surface meshing of the model without any errors and also create an enclosure around it representing the wind tunnel section

Process:

The model given in the challenge is symmetrical so to clean the geometry of the model in a time-efficient manner, the geometrical errors of one-half of the model are cleaned and the model is mirrored and meshed

    

After deleting one portion as can be seen in the figure the cons of the model don't have the proper resolution to depict the shape of the model so the resolution is increased by setting the perimeter in the length tool to 1mm.

   

After increasing the resolution the geometry of the model is cleaned using various tools and the snapshots comparing the cleaned geometry and the original model of the various parts are shown below

Grill 1:

Grill 2

Grill 3:

Tires

Logo

Lock:

Body, Windows, and Floor:

After cleaning up the geometry using the check manager tool the geometry of the model is verified for any penetration errors and cons errors other than single cons. 

And then the half portion of the model except the silencer and logo is mirrored using the transform tool with 3 points plane mirror and all the remaining single cons errors are cleaned up and again the geometry is verified

After completing the cleanup the model is segregated into different parts using the PID manager

And then as the challenge requires the surface meshing of the different parts to be performed it is done according to the resolution mentioned for the different parts and then the mesh is verified for any off elements is improved to reduce the off elements to 0. The snapshots of the meshed surfaces are shared below

And then the wind tunnel with the specified distance between the surfaces is prepared i.e 3 times the height of the car which is 310 surface and 4 times the car length of the car which is 1310 for the front surface and the rear surface it is 6 times the length of the car and then the side walls are kept at the distance same as the width of the car which is 525 and the bottom surface are near to the bottom of the car.

 and the surface mesh of the bottom surface is kept at 20 mm and that of the top surface is 100 using the spacing tool the length of the cons of the side, front and rear surfaces are spaced as it is increasing from the bottom to the upper surface with initial cons being of 20mm and the final being 100 mm and the rest of the cons from the bottom to the top surface would increase with a factor of 1.2

Bottom Surface

Top Surface

 Side Walls

         

Link For the completed Model file:

https://drive.google.com/file/d/1hPQRxPck3ZQYDJGcrQDBTPp9AHNxE4Yc/view?usp=sharing