Project 1 : CFD Meshing for Tesla Cyber Truck

AIM:

For the given model, to check and solve all geometrical errors on half portion and Assign appropriate PIDs and to perform meshing with the given Target length and element Quality criteria. After meshing the half model to do symmetry to the other side.

DESCRIPTION:

PROCEDURE FOLLOWED:

1. The Tesla cyber truck model is loaded in to ANSA software.
2. Then a Topo clean up is done first using topo tool and the single / triple cons are found.
3. The errors are elemenated accordingly with the model.
4. Then the geometry checks is performed for the mode.
5. Then for each compoenent with varying target lengths the meshing is performed.
6. Then the wind tunnel is created accordingly.
7. Wind tunnel is then meshed.
8. Then the vloumetric mesh is performed keeping the required volumes i.e volume between the truck and the tunnel for CFD and other volumes are deleted.
9. Thus, the experiment is completed.

TOPO/GEOMETRY CLEANUP:

Loading the model in the ANSA we see as follows

Doing topo to the model

we see change into double, single and triple cons

Now doing the con resolution to the model with Meshing then Length>perimeters with 1mm and macros with 1mm

we see a good geometry model now as follows

Now fixing the single cons present in the model

Filling the gaps using coons

creating surfaces with other single cons

Filling the hole using fill hole

We see that tyres are not part of the vehicle volume

So we have the closed volume for the truck which is considered as 1, 2 we have separated volumes for tyres and then we create the wind tunnel volume between the truck and the wind tunnel

Now checking the geometry for the model using 'geometry checks'

Fixing the above shown errors

Using topo to check will it fix the single cons

Now we see two single cons with some triple cons

Now again checking geometry checks after eliminating errors

we see two triple cons which are acceptable where three surfaces are joining

Assigning the PIDs for the model as follows

For windows

For sunroof

For tyres and rims

For rear lights

For front lights

For bed roof

For body

MESHING

Giving quality criteria for the bedroof as follows and with target length of 4mm

For sun roof with target length 4mm

For tyres and rims with target length 3mm

For rear and front lights with 3mm target length

For windows with 5mm target length

For body with 4mm target length

The complete mesh for the model looks as follows

WIND TUNNEL CREATION:

Now creating the wind tunnel

Measuring distance between two extreme nodes

Its approx 5825mm

So front end of wind tunnel should be 4X distance from front node

for rear face of wind tunnel should be 6X distance from rear node

for top face 3X and bottom face near to wheels with some gap

side faces from top view to be X distance

creating a point at bottom of truck as follows with 400mm in -ve z-direction i.e bottom

now making at point at front end to make 4X from there as follows i.e (4x5825)+890 =24190mm from point created

The point is created as follows

Now for rear side at 6X distance 6x5825+4905=39855mm to rear side

It is created as follows

Now for top end with 3X i.e 3x5825=17475mm to top

Now for side faces of wind tunnel with x diatance i.e 5825mm

Using curves>create to create the bottom surface of wind tunnel

then using New>COONS to create surface

Measuring vertical distance of the truck is 1442mm

so top tunnel face with 3x5825+1442=18917mm

Using faces>offset

Creating other surfaces as follows

Assigning PIDs for tunnel

Now meshing

Top surface with 100mm and bottom surface with 20mm

Using spacing tool

So meshing for the wind tunnel along with model is generated

VOLUMETRIC MESHING:

Now doing the volumetric meshing for wind tunnel

we only need the volume between model and tunnel, so checking for it and deleting the other volumes.

so this is the below volume which we basically need

TOOLS USED:

1. Faces>New>COONS tool to make the surface
2. Curve2Con to fix the con location
3. Cons>cut to create the cut or to delete the cuts in model
4. Hotpoints> multi-Project to project the hot point on the face required
5. Fine tool > to make the model finer in geometry
6. Mesh>Length>perimeter to give length for perimeters for meshing
7. Mesh>Length>macros to give length for macros/faces for meshing
8. meshing>spacing to give varying length mesh size
9. Mesh>Reconstruct> To rearrange the elements in the meshing and avoid the skewness, min length, max length errors
10. Topo>faces>Project cut> to cut the surface in 90 degrees from hotpoint to con
11. Topo>relative point To create the point in the space at in any direction
12. Mesh>Spot Mesh tool to mesh the visible on screen/ with select option
13. Mesh>move grids to resolve the skewness, Min length, Max length errors.
14. Topo>Release to release the con into single cons
15. Topo tool to make the two surface double con/ three surface into triple con

THINGS LEARNED:

1. Learned how to perform the topo/geometry clean up for the mode.
2. How to eliminate the con erros.
3. How to assign the PIDs required.
4. How to mesh for different components with different target lengths.
5. How to perform the volumetric mesh.

CONCLUSION:

Thus the surface mesh with Tria elements for the model and the wind tunnel has been generated successfully.

FILE LINK

https://drive.google.com/file/d/1EqotfJB3Ur_WdTbkW1J3DUns-ngAWqg4/view?usp=sharing