Week 4 Challenge : CFD Meshing for BMW car

CFD Meshing for BMW car

Project Contents :

1. Surface Clean-up

a) Merged surfaces of different PID'S

b) Extended intersecting surfaces

c) Improper profiled surfaces

d) Single CON clean-up

e) Tripple CON clean-up

f) Intersected-merged surfaces

g) Filling Gaps and holes

2. Symmetric profile generation

3. Surface Meshing for all PID's with respect to given target lengths

a) Dealing with OFF ELEMENTS

b) Methods and application of Mesh Freezing

c) Ultimate usage of Quality Criterias

d) Moving Grids

4. Generation of Wind Tunnel of given dimension

a) Optimum wind tunnel dimensions

b) Creating the Wind tunnel surfaces in ANSA using TOPO tools

5. Meshing Wind tunnel and variable meshing methodologies for efficient computation

6. Volumetric Meshing - Initiation and defining the required volumes for CFD Meshing

Surface Clean-Up :

a) Merged surfaces of different PID'S

Go to Delete > Select the right cross hatch of unwanted PID and delete it

Similarly perform this opeartion for all PIDs.

NOTE

One must be careful while deleting the surface PIDs, where only necessary PIDs have to be kept

Seperated SINGLE CON Treatment :

Go to CONS > PASTE > Click on the seperated Single CONS > Middle Click

Deleting unwanted surfaces and creating new surfaces:

Go to Delete > Select the right cross hatch of unwanted PID and delete it

Go to NEW > COONS > Select the CONS of surface to be prepared > Centre Click on Mouse (Preview) > Centre Click to execute the surface

Similar CASES :

Go to Delete > Select the right cross hatch of unwanted PID and delete it

Merged CONS treatment :

Zoom inside carefully to select the Single CON > Go to Delete > Select the right cross hatch of unwanted PID and delete it

Now keeping these tools as basics

Part wise surface Cleanup :

1. SIDE AIR INTAKE MANIFOLD

2. CENTRAL AIR INTAKE MANIFOLD

3. KIDNEY GRILLS

4. HEADLAMPS

5. OVRM (Optical Rear View Mirror)

6. Wheels

II - Symmetric Profile Generation :

Go to Transform > Copy > Select the Entity and drag all the PIDs > Go to Symmetry > Mirror 3 point Plane > Now Choose 3 points on the edge of the symmetrical plane of the Body > Apply > Finish

III Surface Meshing for all Components :

Target Lengths for all the PIDs

1. Wheels & Tires:

2. Logo:

3. Air Manifolds & Kidney Grill

4. Body :

5. ORVM :

6. Exhaust :

Wind-Tunnel Dimensions :

Distance from the centre to the the front grills x = 1306

1. Distance from the centre of the car to Front side of Wind tunnel = 4*(x) = 5875

2. Distance from the centre of the car to Back side of Wind tunnel = 6*(x) = 8480

3. Distance from the centre of the car to Roof of Wind Tunnel = 3*(x) = 4323

Area of Interest :

Variable Meshing for saving computational time :

Go to Mesh > Perimeteres > Biasing > Geometric > dmin = 10 > dmax = 100 > OK

ANSA Part File for evaluation :