Week 4 Challenge : CFD Meshing for BMW car
Aim:For the given model, check and solve all geometrical errors on half portion and Assign appropriate PIDs and Perform meshing with the given Target length and element Quality criteria. After meshing the half model, Do symmetry to the other side and create and mesh wind tunnel.
Introduction:
Bayerische Motoren Werke AG, known as BMW, is a German multinational manufacturer of performance luxury vehicles headquartered in munich, bavaria, Germany.
Automobiles are marketed under the brands BMW and motorcycles are marketed under the brand BMW Motorrad. In 2017, BMW was the world's fourteenth-largest producer of motor vehicles, with 2,279,503 vehicles produced. The company has significant motor-sport history, especially in touring cars, sports cars.
BMW is headquartered in Munich and produces motor vehicles in Germany, Brazil, China, India, Mexico, the Netherlands, South Africa, the United Kingdom, and the United States. The Quandt family is a long-term shareholder of the company (with the remaining shares owned by public float), following investments by the brothers Herbert and Harald Quandt in 1959 which saved the company from bankruptcy.
Procedure:
step 1: import the model.
step 2: select half section of the car and the delete the select half since the most of the components are symmetery to selected half section.
step 3: analyze and solve single cons, triple cons on the model, for easy checking and solving choose particular components such grills, rims and tyres etc, and perform "!not" operation to solve.
grills
rims and tyres.
step 4:we need to have single volume inside the car in order to achieve that, delete some components inside the car which has the possibility to create new volumes such as triple and single cons.
step 5: delete the overlapping surfaces and surafaces which will affect meshing processes.
overlapping and unwanted surafaces. solved model.
step 6: After solving all the single and triple cons, check the geometry, neglect the single cons as shown below since we are going to perform symmetry operation.
step 7: Start assigning the PID's to the components.
step 8: check for any geometrical cleanup for each PID's corresponding to mesh target length assigned to each component.
step 9: After doing the geometrical cleanup start with 2D meshing
step 10:follow the below criteria for quality of each component and perform below steps
- assign mesh parameters with quality criteria.
- perform spot mesh
- do reconstruction operation in order to identify the irregularities and solve them.
logo,grill- target length=1mm
Window,Rims and Tyres,Optical Rear view mirror-target length - 2 mm
step 11: After meshing all the surfaces, do symmetry using transform-copy-symmetry-3 point mirror plane and perform geometry check of the car.
step 12: global variable to be defined for whole model in order solve the off elements.
step 13: create relative points for wind tunnel as per standard such as let length of car be 'x'mm distance so the distance from front end point is 4x mm,distance from rear end point is 6x mm, distance from top end is 3x mm and width should be length of the car for creating wind tunnel.
step 14: create new faces for wind tunnel and delete the curves and create and assign PID's for the faces.
step 15: perform 2D mesh for the wind tunnel with top suface mesh length =100mm,base surface length=20mm and for side, front, rear surfaces use spacing command to define the range of mesh from bottom to top.
step 16: perform volmetric mesh for the wind tunnel.
Learning outcomes:
- Were able to learn advanced Topology cleanup to define volumes.
- Variable Surface meshing part by part
- Solving quality failed elements as per Quality criteria
- Symmetry operation for surface and mesh elements
- Wind Tunnel Creation
- CFD Meshing for Wind tunnel
Results:For the given model, all geometrical errors on half portion were checked and solved and Assigned appropriate PIDs and Performed meshing with the given Target length and element Quality criteria. After meshing the half model, symmetry to the other side has been performed, wind tunnel was created and 2D suraface mesh was done on the wind tunnel.
https://drive.google.com/file/d/1shZoUx8FnMJFN_HvscyHxWtxixQMjW8y/view?usp=share_link