Project 1 : CFD Meshing for Tesla Cyber Truck

Project 1 : CFD Meshing for Tesla Cyber Truck

Aim:To perform CFD meshing for the given geometrical model of the Tesla Cyber Truck.
To check and to solve all geometrical errors on half portion and to assign appropriate PIDs.
To perform meshing with the appropriate target length and element quality criteria.
After meshing the half model, to do symmetric transformation to the other side.

Target lengths for the different parts of a model are as follow:

1. Body - 6 mm
2. Lights - 4 mm
3. Grills - 4 mm
4. Tyres - 2 mm
5. Window - 5 mm
6. Cover - 5 mm

References for Quality Criterias are chosen on the basis of size of model and guidelines from previous video lectures.

To mesh Wind tunnel volume with tetra elements.

Steps for Meshing of geometric model of the Tesla Cyber Truck:

1. To refine the mesh lengths and macros of the given model.
   
   

   i)	The original mesh lengths of model are set to higher Thus some finer features are not captured correctly.	ii)	To refine the mesh lengths. Change the Mesh>Length>Perimeters to 6 mm
   iii)	To refine the mesh lengths. Change the Mesh>Length>Macros to 6 mm	iv)	The final refined model. The finer features are captured with greater accuracy.

2. To cut the geometric model into half for the centrally symmetric components.
   
   

   i)	The original model has the central axis symmetry when looking from the front of the truck. The truck body, windows, cover, lights and grills are symmetric about central axis.		ii)	Thus to reduce the efforts we will work on the half of the symmetric model.
   iii)	The front view to show vertical axis symmetry.		iv)	The back view to show verical axis symmetry.
   v)	The model after drawing the centreline.		vi)	The model after removing the symmetric half .By using delete command and selecting required portion of the model.

3. Strategy for the geometric clean up of the whole model and list of surfaces and volumes to be retained.
   
   

   i)	The original model is having multiple seperate volumes and surfaces for internal features. As we are going to need the external feature for CFD study of the flow over a car in wind tunnel.		ii)	Thus we will make one single internal volume for truck body which will be closed after the copying the symmetric part. So the componentswhich are in direct contact with truck body will be cleaned in such a way that they will become the integral part of the volume of the truck body.
   iii)	These components are the tyres which will be integrated with the truck body volume. Thus the surfaces of the same cleaned accordingly. Interconnecting surfaces with the cae body are deleted to make in single volume.		iv)	Similarly the lights, grills,windows,covers which are having internal surfaces for internal features are cleaned such that the internalvolume of the car is maintained and no extra seperate volume is created.
   v)	The list of volumes to be retained for sureface meshing		vi)	Surface Meshing.
   	Truck body internal volume with grills,lights,cover and windows. The internal volume tyres. (4 numbers in final model)			The components are surface meshed as per chosen target lengths and quality criteria. There should not be any off element in the model.

   
   
   
4. Geometric clean up of the grills.
   
   

   i)	The isolated internal view for the all grills on the half model showing the geometric anamolies with extra surfaces and extra edges.		ii)	The internal view of the grills after geometric clean up.

   
   
   
5. Geometric clean up of the lights.
   
   

   i)	The isolated view of front lights showing the internal features and multiple single cons.		ii)	The isolated view of back lights showing the internal features and multiple single cons.
   iii)	The isolated external view of front lights after geometric clean up		iv)	The back lights are cleaned from inside to make single volume for internal truck body.The final internal view of the back lights.

6. Geometric clean up of the windows.
   
   

   i)	The external view of the windows showing multiple single cons.		ii)	The isolated external view of the windows after the geometric clean up.

   
   
   
7. Geometric clean up of the Cover.
   
   

   i)	The external view of the missing cover.		ii)	The isolated external view of the cover after geometric clean up that is after creating the cover surface.

   
   
   
8. Geometric clean up of the tyres.
   
   

   i)	The external isolated view of the rims and tyres showing single cons.		ii)	The isolated external view of the rims and tyres after geometric clean up.
   iii)	The surfaces of wheel axel from the tyre end are deleted and the surfaces from truck body end are retained and assigned to truck body PID. Same has been shown in the figure from (ii) thus the triple con can be seen at the junction.

9. Geometric clean up of the Truck body.
   

   i)	The external front view of the truck body showing the multiple single cons and triple cons at the conjuction of grills,lights and windows.		ii)	The isolated external side view of the truck body showing the multiple single cons at the conjuction of grills, lights and windows. Also the very thin surfaces are be observed into the body at various positions.
   iii)	The external side view of the truck body from rear angle showing the multiple single cons and triple cons at the conjuction of lights and covers.		iv)	The internal view of the truck body showing single cons and triple cons along with extra surfaces.
   v)	The internal view of the truck body showing single cons along with missing extra surfaces.		vi)	The internal view of the truck body showing single cons and triple cons along missing extra surfaces.
   vii)	The external front view of the truck body after geometric clean up.		viii)	The external side view of the truck body showing removal of the extra surfaces frrom the wheel spaces and resolving multiple triple and single cons.
   ix)	The external side view from the rear angle showing geometric clean up of the truck body.		x)	The internal view of the truck body showing resolution of the multiple triple cons and removal of extra surfaces.
   xi)	The recreation of the bottom surfaces of the truck body can seen in the following image. Extra surfaces have been removed.		xii)	The whole internal view of the truck body showing recreated bottom surfaces and internal geometric clean up.
   xiii)	The front view showing grills, lights along with truck body.		xiv)	The rear view of the truck body showing geometric clean up to avoid quality criteria failure due to the minimum length.

   
   
   
10. PID assignment
    
    

    i)	Assigning the PID for grills.		ii)	Assigning the PID for lights.
    iii)	Assigning the PID for windows.		iv)	Assigning the PID for covers.
    v)	Assigning the PID for rims and tyres.		vi)	Assigning the PID for truck body.

    
    
    
11. Surface meshing of the grills with desired target lengths and quality.
    
    

    a)	All of the surface meshes are generated by isolating the respective PID then assigning the desired quality criteria along with mesh parameters.		b)	Into the mesh deck mesh perimeters and macros are assigned and mesh is generated with spotmesh-visible. Mesh is reconstructed whenever needed to minimize the numeber of off elements.
    i)	The quality criteria for surface meshing of the grills.		ii)	The mesh parameters for surface meshing of the grills.
    iii)	The view of the surface mesh of the grill.		iv)	The hidden view of the surface mesh of the grills for confirmation of quality criteria.

    
    
    
12. Surface meshing of the lights with desired target lengths and quality.
    
    

    i)	The quality criteria for the surface meshing of the lights.		ii)	The mesh parameters for the surface meshing of the lights.
    iii)	The external view of the surface mesh of the front light.		iv)	The hidden view of the surface mesh of the front light.

13. Surface meshing of the windows with desired target lengths and quality.
    
    

    i)	The quality criteria for the surface mesh of the windows.		ii)	The mesh parameters for the surface mesh of the windows.
    iii)	The isolated external view of the windows surface mesh satisfying the desired quality criteria.		iv)	The isolated hidden view of the windows surface mesh satisfying the desired quality criteria.

    
    
    
14. Surface meshing of the cover with desired target lengths and quality.
    
    

    i)	The quality criteria for the surface mesh of the cover.		ii)	The mesh parameters for the surface mesh of the cover.
    iii)	The external view of the surface mesh of the cover satisfying the desired qualtity criteria.		iv)	The another view of the surface mesh of the cover satisfying the desired qualtity criteria

    
    
    
15. Surface meshing of the tyres with desired target lengths and quality.
    
    

    i)	The quality criteria for the surface mesh of the tyres.		ii)	The mesh parameters for the surface mesh of the tyres.
    iii)	The view of the tyres showing surface mesh satisfying the desired quality criteria.		iv)	The hidden view of the tyres showing surface mesh satisfying the desired quality criteria.

    
    
    
16. Surface meshing of the the cybertruck body with desired target lengths and quality.
    
    

    i)	The quality criteria for the surface mesh of the truck body.		ii)	The mesh parameters for the surface mesh of the truck body.
    iii)	The necessary cons are selected for assigning the mesh perimeters. Macros are not assigned for this PID as it has been connected with multiple PIDs with different macros.		iv)	The mesh is generated with the spotmesh visible. To minimize the off the elements,the mesh has been reconstructed. After reconstructing the mesh the count of off elements has been reduced significantly.
    v)	Most of the off elemetns are present at the conjection of the truck body with the grills,lights and windows.		vi)	The off elements are eliminated by move and paste node command along with split elements command, by this way the off elements are eliminated.
    vii)	The Final View of the surface mesh of the truckbody.		viii)	The hidden view of mesh showing corfirmation of quality criteria.

    
    
    
17. To copy the model on the other side with the symmetry option and its geometric clean up
    
    

    i)	The half car model with full surface mesh, without any off element. The off elements are shown in the following figure due to different quality criteia and mesh parameters assigned for different PIDs.		ii)	The half truck model has now been replicated on other side with transform>copy>Entities>Symmetry command.
    iii)	For the symmetry transformation 3 points from the plane of symmetry has been selected.		iv)	After finishing the symmetry transformation commmand. The full truck model is as shown below showing some single cons not connected properly to make double con. Same has been resolved using cons>paste command.
    v)	The finished full truck model - Front view.		vi)	The finished full truck model - Top view.
    vii)	The finished full truck model - Bottom view.		viii)	The finished full truck model - Rear view.
    	By this way the fully surface meshed truck model has been created.			The approximate centre of the bottom surface has been marked and point has been inserted at the same place.

    
    
18. To creat wind tunnel.
    
    

    i)	The length=5900 mm, height=1530 mm and width=2030 mm of the Tesla Cyber Truck has been measured. Same has been depicted here.		ii)	The reference point for the bottom surface for wind tunnel has been inserted using Topo>Points>Relative method at the 375 mm below the bottom surface of the car. Same has been shown below.
    iii)	Similarly the reference point for front surface of wind tunnel has been inserted using Topo>points>relative method at the distance of 4 times of length of car from leading edge of the car. i.e. at the distance of 26550 in the -'ve Y direction.		iv)	Similarly the reference point for rear surface of wind tunnel has been inserted using Topo>points>relative method at the distance of 6 times of length of car from trailing edge of the car. i.e. at the distance of 38350 mm in the +'ve Y direction.
    v)	Similarly the reference points for side surface of wind tunnel has been inserted using Topo>points>relative method at the distance of 1 times of length of car from side edge of the car. i.e. at the distance of 6915 mm in the -'ve X direction.		vi)	Similarly the reference points for other side surface of wind tunnel has been inserted using Topo>points>relative method at the distance of 1 times of length of car from side edge of the car. i.e. at the distance of 6915 mm in the +'ve X direction.
    vii)	The all reference points inserted are shown in the figure below.		viii)	The curves have been generated using inserted points to creat bottom surface, as shown below using curves>create command.
    ix)	The bottom surface has been generated using coons command.		x)	Respective PID has been created for bottom surface.
    xi)	The created points and curves have been deleted once the bottom surface has been created.		xii)	The top surface of the wind tunnel has been created using Topo>faces>offset command. By using offseting value as 20105 mm (3 times of length above the top surface) and retaining the original surface. PID has been assigned to TopSurface_tunnel.
    xiii)	The wind tunnel rear surface has been created using coons command and selectecting the respective edges of the bottom and top tunnel surfaces. PID has been assigned to RearSurface_Tunnel.		xiv)	The wind tunnel front surface has been created using coons command and selectecting the respective edges of the bottom and top tunnel surfaces.PID has been assigned to FrontSurface_Tunnel.
    xv)	The wind tunnel both of the side surface has been created using coons command and selectecting the respective edges of the already created tunnel surfaces.PID has been assigned to SideSurface_Tunnel.		xvi)	The wireframe view of the whole geometry after assigning all PIDs.

    
    
    
19. Surface meshing of the wind tunnel surfaces with desired target lengths and quality.
    
    

    i)	The quality criteria for surface mesh of bottom tunnel surface.		ii)	Mesh parameters for bottom tunnel surface.
    iii)	The Mesh>Length>Perimeters for bottom tunnel surface.		iv)	The Mesh>Length>Macros for bottom tunnel surface.
    v)	The surface mesh for bottom tunnel surface has been genertated using spotmesh visible.		vi)	The quality criteria for surface mesh of top tunnel surface.
    vii)	Mesh parameters for top tunnel surface.		viii)	The Mesh>Length>Perimeters for top tunnel surface.
    ix)	The Mesh>Length>Macros for top tunnel surface.		x)	The surface mesh for top tunnel surface has been genertated using spotmesh visible.
    xi)	Image showing the front, rear and two side surfaces remained unmeshed.		xii)	The shown settings for Mesh>Perimeters>Spacing>Geometric have been applied to the respective four edges.
    xiii)	The rear tunnel surface has been surface meshed using spotmesh visible.		xiv)	The front tunnel surface has been surface meshed using spotmesh visible.
    xv)	The one of the side tunnel surface has been surface meshed using spotmesh visible.		xvi)	Similarly the other side tunnel surface has been surface meshed using spotmesh visible.
    xvii)	The all tunnel surfaces have been surface meshed.		xviii)	The wireframe view of the whole model.

    
    
    
20. Volume Meshing of the wind tunnel volume.
    
    

    a)	The model with all surfaces meshed with the desired quality criteria is taken for the volume meshing.		b)	To auto detect the various volumes from the model using Volume>Define command on whole database.
    i)	Now after auto detecting the volumes, all possible volumes are detected and enlisted as shown below.		ii)	The volumes resposible for tyres are shown here.
    iii)	The truck body internal volume has been shown here.		iv)	The volume of wind tunnel except the truck and other associated volumes are shown here. This is the required volume for volume meshing.
    v)	Other volumes have been deleted using right click delete command.		vi)	And the respective volume has been volume meshed using right click remesh command.The type has been selected as Tetra CFD.
    vii)	Full cross sectional view of the wind tunnel volume.		viii)	Transverse and longitudinal cross sectional view showing cross section front tyre and the truck body.
    ix)	The the wiremesh view whole wind tunnel volume.		x)	The whole wind tunnel volume without geometry.
    I)	As Volumetric Mesh model compressed file is around 102 MB in size.It can't be uploaded here.So kindly consider the google drive link to download it. The link is as follows		II)	Please find the model compressed file till the surface Meshing of thewind tunnel attached herewith. Link of the same is as follows.
    	https://drive.google.com/file/d/1f2wfwPF2n1Gxh1QIV5C6kpyw EHxFkxuI/view?usp=sharing			https://drive.google.com/file/d/16kzRsRJ2Y773zWANiHpxvbj sZmNeOHwX/view?usp=sharing
    	Conclusions
    i)	Thus the Tesla Cybertruck geometric model has been succesfully surface meshed using given appropriate procedure.		ii)	The wind tunnel has its own dimesions respective of the body around which tunnel has been created. Learned and understand those concept.
    iii)	Thus the wind tunnel has been successfully volume meshed around the geometric model of Tesla Cybertruck.		iv)