Week 4 Challenge : CFD Meshing for BMW car

BMW Car Meshing using ANSA

Aim: To mesh BMW Car for different target lengths.

Objective: Target lengths for the different parts of a model are as follow:

1. Body - 3 mm
2. Lights - 4 mm
3. Grills - 1 mm
4. Rims and Tyres - 2 mm
5. Optical Rear view mirror - 2 mm
6. Window - 2 mm
7. Silencer - 3 mm
8. Logo - 1 mm

Procedure:

Open file in the ANSA

File --> open --> ___.ansa

1. Rough clean-up

Open mesh select length (select model)--> Perimeters --> 1 mm.

length --> macros(select model) --> 1mm.

The model will get finer to distance of 1mm.

2. Delete half side of model we can further symmetry the other side after clean-up.

3. Diagnose the model for every part individually and to do clean-up deleting unnecessary parts and fitting new faces as required.

Use project to extend cons to surfaces/faces.

Project--> select cons--> select face--> apply

Use paste to attach two cons

Paste--> select cons--> apply

creating faces

New-->coons/ fitted--> select single cons--> apply (choosing appropriate preview)

Intersection: To intersect two surfaces

Intersect --> select first surface --> select second surface

Delete the remaining parts.

Keeping only required faces

Delete not required surfaces in logo

Delete not required faces in windows

Extend: To extend the surfaces

Extend --> select cons --> select face --> apply

Delete the inside surfaces forming triple cons

Perform geometry checks:

check for any other errors than these single cons. (Later use this for symmetry)

Assigning PIDs:

Create PIDs as shown

New-->Shell property --> (assign name) --> ok

Select PID --> apply --> select parts accordingly --> (middle click)

Deleting unnecessary PIDs

Compress --> ok

Meshing:

1. To check for any surfaces between with distance less than 1mm.

2. Remove cut lines to maintain quality mesh criteria.

At grills:

4.

Meshing all the parts:

Assign Mesh quality criteria

Mesh parameters:

Mesh accordingly as per the given target lengths and apply freeze.

Final mesh:

Copy the half part to other side using transfer:

Select points for symmetry.

Final view:

To create wind tunnel:

Create face using 4 points at approppriate distance from Car

offset to create face on upper side

create facs on all sides.

Meshing the tunnel

Assigning wind tunnel PIDs

Volume inside wind tunnel.

Conclusion:

All the parts are meshed with desired target lengths assigning PIDs.

Wind tunnel created for BMW Car.

(BMW Car link:)

https://drive.google.com/file/d/1-WF1eN0SSrcV7P_4WmKjDDmTPRz9Dv5j/view?usp=sharing