Project 1 : CFD Meshing for Tesla Cyber Truck

Aim: To perform the given model of tesla’s Cyber truck and solve all Geometrical errors and  Assign appropriate PID’s . Perform meshing with the suitable target length and elements Quality Criteria and also create a wing tunnel and perform a volumetric mesh.

Objective:

* Target length for the different parts of a model can be decided by our own. Finer mesh will give good results and will compromise with the longer processing time.

* Meshing wind tunnel volume with tetra elements may take upto 2 days of time. So that is not compulsory  to perform . As this is a major project , It is advisable to mesh that completely by taking some days of time.Write a detailed report for the same.

* Note: All the 2D Elements ( Trias) in your model should clear the quality Criteria ( I.e off elements should be zero) . Depending upon this you will be awarded  marks.

Model Set up:

 

Wire Frame mode:

Procedure:

*  TOPO/ Geometry Clean up

* Upload the ANSA file in to GUI to perform topo/ clean and Meshing on the later stages

* Go to mesh and choose length and enter 1mm under perimeters to smoothen the sharp curves of the car and give it a fine look.

*  We can now start with the TOPO clean -up by removing the single and unnecessary triple cons .First click on topo and box select the entire to identify or joins any unjoined single cons or triple cons so that we can identify the required clean -up accordingly.

* Since the car is symmetric from the middle to any end. We can see delete one side of the  car and perform the necessary operations on the car and use symmetry option to produce the complete car.

 To delete half model using tool cut plane:

Deleting the Half model:

Symmetirc created:

*  After performing the symmetric  for the entire half  model We need to perform geometry Checks to find small cracks are unchecked extra faces which is not good for the geometry , There fore we need to perform checks and clean the geometry accordingly.

 

There fore the cracks and single cons are present we need to clean the geometry

Clearing the intersecton part from trcuk front side

Clearing the intersection between tyres:

Geometry Error and Intersection Error Cleared:

Once the geometry is checked and has no errors , we can now assign names to different components Using PID’s.

After Assign the names , we now to choose the quality criteria method, 

Using The measure tool We can calculate the smallest distance between to cons or hot  points and depending upon that , We can assign our minimum and Maximum length accordingly in the mesh parameters , if we do not do this we can get fail mesh.

 Mesh Length:

1.Tyres-2 mmBody-3 mm

2. Body-3 mm

Surface Meshing:

We need to mesh the components individually since the given mesh targets are different for each PID’s regions.

Assign the mesh parameters and Quality parameters for each PID accordingly . Assigning the correct min and max length will reduce mesh failure and off elements.

After Meshing we can choose re-construct under shell mesh to reduce the off- elements . And later the remaining off elements can be edited manually.

1. TYRES:

Mesh Parameters:

Tyres Meshing Completed:

2.Body:

Quality Parameters:

Mesh Parameters:

Body Mesh Completed:

 

Performing Symmetry on the Car Model:

Perform symmetry under transform option to create a extract same opposite body of the car to create a full body car.

After choosing the model , middle click mouse , we get a  window , choose symmetry and choose mirror 3 points plane and choose 3 points on the edge to be performed symmetry.

After choosing 3 points middle click twice and then symmetry is performed , click middle click again to confirm the geometry and complete the process.

There will be few single cons present near the middle section, Use paste or other tools to solve the problem.

 Post Symmetry the geometry check up has perfomed to conform:

 

Creating Wind Tunnel:

First We need to create reference points wind tunnel surfaces.

Select relative under points in TOPO Mode , Create a point below the car taking one reference point and entering the correct values.

And Calculating the wind tunnel dimensions appropriately , We can create the wind tunnel accurately.

The wind tunnel dimensions are :

( Standard Distance of the tunnel wrt to Model)

 Car Model Dimension (x):5740 mm

Front surface distance( from Reference Point):----4X

Back surface distance( from Reference Point):----6X

Top Surface distance( from Reference Point):----3X

After Creating the bottom surface use the curves for having the reference of cons , We can delete all the points and curves.

Create all the other wind tunnel surface using the new surface option.

 

Finally Wind tunnel is created :

Surface Meshing of wind tunnel:

We need to apply surface meshing depending upon the mesh length near the truck and regions far away from it.

Therefore we need to apply different mesh lengths at the bottom and top wind tunnel surfaces.

We need to use spacing tool option to have a mesh length varying from the small mesh length size to larger mesh length.

Surface mesh can be achieved by doing this accordingly

Final mesh:

Learning Out Comes:

Learn the Complete CFD Process.

Performed various topo clean-up using different tools.

Understood the needs of double cons and removing unnecessary triple and single cons.

The use of symmetry helps in reducing the work time and helps in having accurate results with less work.

Create surfaces using the reference hot points by using relative points.

Surface mesh for different components and with varying the mesh lengths.

Using Spacing option in surface mesh helps in having varying mesh lengths along the surfaces.

Using reconstruct option to reduce off elements to a level where can edit it manually.

Use the mesh modified tool like move , split and smooth options.

Result Link:

 https://drive.google.com/file/d/1TXoNX8SS9INIkoP7QicEjnAIw9wfIHEN/view?usp=sharing

Conclusion:

Cyber truck car model is topo cleaned -up and surface mesh performed.

Wind tunnel is created and surface mesh is performed with  reference car model size  

Different volume of the car model is created since the tyres are not connected to the car body

Single volume is created of the car body so that it can be avoided at one go with volumetric mesh.

Required physics tests can be performed on the wind tunnel volume model after volumetric mesh successfully.