[gavaskarkrishnan]

Hi All,

Need to do CFD for a Automotive Bake Oven used for heating Car BiW [Body in White Part] component.

Here are the details of the problem:

Car Body Moves in a long enclosed Oven tunnel of 300ft and the walls of the tunnel has slots at regular internals through the tunnel. These slots are placed on the wall facing the side body of the car. Air flows through this slots at consider 10 m/s with air temperature at 350 F. Car continuously moves into the tunnel at a very slow speed and passes through the slots blowing air continuously. Now I am planning to do a transient simulation of this problem. Car Body's are continuously lined up in the tunnel one after the other. Need to study the temperature and flow distribution of the car surface as it moves into the tunnel.

I was considering to take just one portion of the car and the surrounding oven tunnel wall with slots to build the cfd model. Then I will separate out a rectangular section of the wall that will contain the slots.Then I would try using moving mesh to move the rectangular section of the wall containing the slots to simulation the moving car condition. Could anyone tell me if this would be the right approach in starccm+. is there any other way of doing this problem without using moving mesh and if in case I end up using moving mesh would this work out. But i think i might have to create a very very long rectangular section with slots to consider running the moving mesh for longer duration.

https://www.youtube.com/watch?v=lOn-w8cvnCs

above video exactly replicates the scenario.

Can anyone tell me the correct approach for this problem and computationally cost effective. let me know your suggestions. Thanks

[me3840]

Using sliding mesh for this would be rather difficult, sliding mesh is better for rotational motions and no displacement.



The video you linked looks like it is immersed boundary, which STAR-CCM+ can't do.


You would be able to do something similar with overset mesh if you so choose, but it would be fairly compute intensive. It is, however, the easiest way to set the problem up.



Another way to do this which might be less expensive would be to create the jets mathematically as a field function. You would probably lose some of the jet detail in the nearfield but it may not matter in the far field. From that perspective you could then just move the jets around a stationary car, but you'd have to think something up for the temperature condition at the inlet and exit.

[gavaskarkrishnan]

By moving mesh I meant that I would be moving a long portion of the recantugar wall with slots along the length of car body... Its like taking a rectangular slice of a wall and moving it. I guess I am wrong. I will have to move the mesh ahead in the wall to move the rectangular block. Ok then using overset mesh can i have the side walls of the rectangular block facing the car with slots exclude from the interface...because I need to give that slot as a velocity inlet or mass flow inlet bc... so only the other faces would be treated as over set mesh interface.. ... I am kinda confused n how to use overset for the rectangular wall block.

Or I can move the entire car using overset which would be very very slow process to solve....

Thanks a lot for your earlier response..

[gavaskarkrishnan]

Also, is there a way to use periodic condition while using the overset...so that if i solve for one car length distance for one cycle and then repeat the same again and again....