Project 1 : CFD Meshing for Tesla Cyber Truck

Aim:

To perform the meshing on Tesla cybertruck model with satisfying the quality criteria with the wind tunnel enclosure. The surface meshing of the wind tunnel is also performed.

Procedure: 

First the model is downloaded and we will observe the geometry errors. We will delete the half part which contains more number of errors, and do the CAD cleanup of the remaining half. There are so many small faces which will be deleted, hence it will have problem in skewness quality criteria. Click on Topo whenever necessary to make sure joints are properly connected. We will make sure that we will have 0 number of geometry errors, warnings and intersection errors. After that we will assign the PIDs. We assign for the windows, tyres and the body. Then we will mirror the half part and perform the meshing. 

For windows and tyres we will give the target length of 2 mm while for body we will give target length of 3 mm. In quality criteria we will enable the skewness, minimum length and maximum length. The skewness is given value of 0.5 mm, minimum length as 0.5 mm and maximum length as 7 mm. After performing meshing of each component we have to freeze it and then perform meshing of next component. Make sure to delete the off elements using improve i.e Reconstuct or Reshape options to have zero off elements.  Thus we will have perform surface meshing of the car model, with total number of triangular elements as 5174045. 

Now we will create the wind tunnel structure, with the front part of car has length of 4x, rear part has length of 6x, side part has length of x each, top part has length of 3x, while for bottom part we will select such that we wont intersect with the tyres. Here x is the length of car i.e, 5760 mm. We will use the relative points option to create the points, then curves are created. Thus the bottom face is created. Then the top face is created using offset option of bottom face. Then we create new faces of side and inlet and outlet faces. Thus the wind tunnel is created. Now we will create the surface meshing of the wind tunnel. 

For bottom face we use target length of 20 mm, with minimum target length of 10 mm and maximum target length of 30 mm. Then we will use the CFD mesh algorithm to generate the mesh. We get total number of triangular elements as 2387036. Then we will do meshing of the top face with target length of 100 mm. Here we use minimum target length of 90 mm and maximum target length of 110 mm. Then we do meshing, we get total number of elements as 177530. Then we will try for remaning sides. Here we use the growing mesh with mesh growing from 20 mm in bottom side to 100 mm in top side. Here we use perimeter spacing and manual option instead of auto cfd in remaining all other cases. We give Dstart as 20 mm and Dlimit as 100 mm. Then perform meshing using CFD algorithm and mesh is created. So surface meshing of wind tunnel is completed.  volumetric mesh is not performed as it involves more than 2 todays to generate the tetrahedral elements. 

The above figure shows the geometry after the geometric cleanup is performed. 

The above figure shows the zero number of errors obtained after the cleanup. 

The above figure shows the wind tunnel enclosure around the car model. 

The above figure shows the PIDs created for all the parts , with the number of elements generated. 

The above figure shows the quality criteria used. 

Learning outcome:

 To perform meshing on Tesla cyber truck with wind tunnel with quality criteria is enabled. Thus we can know the amount of off elements which are generated, and will be knowing how to remove the off elements using improve option of reconstruct , reshape etc. 

Results:

The above fig shows the meshing operation performed on the window. 

The above fig shows the meshing operation performed on the window in zoomed position. 

The above fig shows the meshing operation performed on the tyres. 

The above fig shows the meshing operation performed on the tyres in zoomed position. 

The above fig shows the meshing operation performed on the body. 

The above fig shows the meshing operation performed on the body in zoomed position. 

The above fig shows the meshing on bottom face of wind tunnel. Target length of 20 mm used.

The above fig shows the meshing on top face of wind tunnel. Target length of 100 mm used.

The meshing of the entire wind tunnel is shown. 

The above figure shows the  surface meshing of the car model with the wind tunnel . We have got total number of triangular elements as 8399961. 

Conclusions:

So the surface meshing of tesla cyber truck along with the wind tunnel is performed. The target lengths are given different for different parts and the quality criteria of skewness, minimum length and maximum length are enabled.