Week 4 Challenge : CFD Meshing for BMW car

Aim: To check and solve all geometrical errors on half portion of the model (Car) and Assign appropriate PIDs. Perform meshing with the given Target length and element Quality criteria. Generating surface mesh of all the PIDs.

Target lengths are specified below.

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:

The 3D model is imported into ANSA software.

Auxiliaries --> Fine to smooth individual surfaces.
Since the model is huge and is a time-consuming process, another method

Mesh --> Perimeters --> Length --> Perimeters & Macros changing Lengths to 1 mm.

switching back to Topo, all surfaces look smooth.

Since the model is symmetrical and to minimize time, the model is deleted (except the logo) exactly half as shown below using the delete option.

Perform a Geometry check so that there are no Single & Double Cons, also Hot points.

Picture

Assigning target length for the parts of the car. measuring the minimum length so that in the mesh parameters & Quality criteria minimum & target lengths are specified.

After getting the minimum lengths of all surfaces, now we can assign Mesh Parameters & Quality criteria & save them n ANSA format for future use.

Grill off elements.

Car body to be meshed with target length 3mm leaving all the cons whichh are in contact with other PIDs.

Reconstruction results in 260 off shell elements and after using commands like Move and paste in Grids --> Mesh reduced to zero.

Before

After

Using transform tool to get other half of the car model with mesh elements.

Transform --> Copy --> Symmetry --> Mirrir 3 points plane --> select 3 points

Transformation option --> Same part --> ok --> Finish to get the complete car model.

Using paste option in Topo model to join 2 halfs of car models.

Creating Wind Tunnel for the model.

Create nodes as per the standards for wind tunnel below and create surfaces.

Conclusion:

1. As per instructions, wind tunnel takes 2 days to create, hence eliminated from the assesment.

2. Use of multiple tools are been practised in this challenge.

ANSA completed model is in below link.

https://1drv.ms/u/s!AgT2OidYkkemgoRbSDWT0X1YyvJefQ?e=z0hbGB