Week 4 Challenge : CFD Meshing for BMW car
Aim: To make the surface mesh and volumetric mesh for BMW car present in the wind tunnel.
Procedure:
1) First of all we need clean up the geometry of the car and then do the mesh. So 1st i have done the clean up using the finner option to see clearly or by length option giving 1 mm as shown in figure to visible in better way. 
2) After getting clear vision, isolating one by one i have cleaned the single cone and triple cone to double cone to get the required geometry. 1st i have done with my logo clearing the single and triple cones and grills and lights and optical rare view mirror and tries and rims and last body i have cleaned with the option called cut , new (to add faces), delete ( deleting the cons and faces ), hot points projetions of cons and extened option, etc are used for cleaning the geometry.
3) After cleaing the geometry, gone for surface meshing as per given guidelines of of each PID. Now, i have assigned my parts to different PIDs like Body, lights,grills, rims & tires, window, silencer, and logo .
4) Now, 1st meshing was done to the logo part with 1mm mesh length surface meshing. silencer with 3mm, window with 2mm, optical rare mirror with 2mm, rims & tries with 2mm and grills with 1mm , lights with 4mm and body with 3mm mesh length is given.
5)Now checking the quality of the mesh by hidden option to check the quality if there to sort by legend colours.
6) Now ready to draw the wind tunnel as per the dimensions, front 4x , back 6x , top 3x , bottom is not required just giving some distance is just see. that x lenght is 1300mm .
7) create the surface for bottom part for the wind tunnel and do offset to get top part and by new option we will get all parts.
8) bottom surface will be given 20mm and top surface will be given 100 mm .
9) now for front surface back surface, and for side surfaces we will use the spacing option such way the from bottom we will increase the element size as we go up by dstart giving 20mm and dlimit to 100mm .
and now we are done with surface meshing for the whole wind tunnel .
Learning Outcomes
1) learned how to clean complex geometry.
2) learned how to mesh the complex geometry.
Result: Done with surface meshing of the BMW car in wind tunnel using ANSA.