Project 1 : CFD Meshing for Tesla Cyber Truck

Aim:

For the given model, check and solve all geometrical errors on full portion of the cyber truck and Assign appropriate PIDs. Perform meshing with the given Target length and element Quality criteria. After meshing the full model, Do V.mesh to wind tunnel and car geometry

1. Target lengths for the different parts of a model are as follow:
2. Body - 10 mm
3. Lights - 5mm
4. Rims and Tyres - 9mm
5. Window & Mirrors - 8 mm
6. Base Surface- 10mm

Procedure:

A)Topo Clearance : (Topo Mode)

• Open the model, it will be in ENT mode initially.
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• Check in Wireframe mode, to view the single cons and triple cons
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• Apply topo feature to the entire model and solve the triple cons.
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• The Cons are unshaped ( not fine ) throughout the entire model. So, Cons resolution has to be increased.
• Among the various options, FINE option can be used but for the entire model it is not advised as it consumes lot of time.
• Short cut method: Under Mesh Deck > Apply Length as 1 mm selecting the entire model.
• Check Single cons and triple cons disabling shadow and enabling wireframe mode to rectify.
• Next is the topo cleanup to make entire model as uni-volume
• Various tools for topo cleanup activities used are:1. Delete 2. Create faces using fitted and coons 3. Paste 4. Inserting hot points 5. Measure 6. Uncut and other Boolean Operations.
• Change the mode from ENT to PID.
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• Peform Geometry Checks before performing topo cleanup
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• Creating New Surfaces: (COONS, FILL HOLE, FITTED)
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B)Assigning PIDs, Setting Quality Criteria & Surface Meshing (Mesh Mode):

• Once the topo clean-up is done and verified the geometry check for single and triple cons
• next follows assigning PIDs
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• Default PIDs for the given model
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• New PIDs are created and surfaces are applied using Apply Option and Selecting appropriate Cross Hatches. Similary various individual PIDs are created.
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• After Assigning PIDs, Surface mesh Operations are initiated for the individual PIDs as per the given mesh target lengths. (Body, Rims and Tyres, Windows and Mirrors, Lights, Base Surface)
• Quality criteria are extracted for PIDs individually through the Measure option identifying minimum & maximum distances in each PIDs
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• Mesh Element: Tria; Minimum length, maximum length, target length, Perimeters & macros length and at last spot mesh selecting the PIDs for Surface Meshing
• Windows and Mirrors (Target Length: 8 mm)
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• Doors (Target Length: 5mm)
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• Lights ( Target Length: 5mm )
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• Tyres & Rims ( Target Lenght: 9mm )
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• Body & Base Surface (Target Length: 10mm)
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• Note: Before Meshing Body, All the other PIDS are freeze to avoid collapse in macros
• Freeze/ Unfreeze > Left Click drag and select the entire model to freeze all macros.

B1) Solving Off Elements: (Using Reconstruct, Improve, Move, Smooth & Split )

• It shows off-elements that fails quality criteria designated with various colors which can be solved using Reconstruct, Move, Smooth and Split Options.

C) Creation of Wind Tunnel & Surface Meshing:

• Measure the Length and Width of the Truck:
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• Under this, the predecessor is the creation of a wind tunnel using:
• 1. Points using Relative Optiosn (Points > Relative)
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• 2. Curves
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• 3. New face creation
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• 4. Assigning different PIDs
• Points are created based on X(=5906mm) which is the distance of whole length of cyber truck in side view using Relative Option under Points.
• Then the points are connected using Create Curves Option.
• Base surface is created at a distance of 750mm using relative point option extracted from bottom of the car.
• Top Surface is created at a distance of 3.5X
• Front and Back Surface created a distance of 4x from the bottom reference point.
• Assign PIDs to all surfaces individually to perform surface meshing.
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• Top surface is meshed with 300mm ( QC: 240 & 360) & Bottom surface with 60mm (QC: 45 & 75) as target length as fine mesh is not needed all over the wind tunnel.
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• Once the top and bottom surface mesh is done, next is the front, rear and lateral surfaces which is meshed using Spacing > Geometric > factor 1.1; dmin: 60 & dlimit :300
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• The variable fine and coarse mesh of wind tunnel is observed using Measure > Node.
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D) Volumetric Mesh: - V.mesh Mode

• Once the surface mesh is done, the geometry is taken to the V.mesh mode to perform volumetric mesh.
• the First step is to detect the volumes using Volumes> Define>Auto Detect > Ok
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• It will auto-detect the unmeshed volumes. Here it is 7 unmeshed volumes
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• On picking each entry, it shows the unmeshed volumes individually.
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• The unwanted detected volumes are deleted and our area of interest is chosen to perform our necessary task. (the volume between Cyber Truck and Wind tunnel)
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Result:

Thus, the Whole operation starting from geometrical clean-up to Volumetric mesh (not meshed) is performed without any errors step by step to the cyber truck geometry and wind tunnel.

As the whole volumetric mesh takes a lot of time (upto 2 days) to produce the result, the progress is halted upto detecting volumes succesfully.

Please find the geometry file link here:

https://drive.google.com/file/d/1uX9sN5zmIpv4dvGX0rqsn0zNiSVIWlFf/view?usp=sharing