How to use internal fan as boundary condition in NX 6?

[72630]

Hello, I am doing a simulation of an airintake using UGS NX 6. The problem is that every time I try to introduce an internal fan in a surface betwen two meshes bodies that are in contact by this surface, the program says that this surface is an external surface so erase it or change it for an outlet/inlet condition. The bodies represent the domain of air with the shape of the ducts. I need to declare a speed inside my air volumen, in the middle of the path, and I don´t know how to do it, I have tried with extrudes planes as surfaces 2d meshed, but it doesn´t work.
Please somebody help me.
Thanks!

 

[cowski]

Get rid of the extra surface(s). The fan will create a potential between your inlet and outlet, use that as your boundary condition on your inlet and/or outlet. For instance, the fan may produce a known pressure drop between the inlet and outlet, or it may cause a certain airflow at the inlet or outlet. Any of these can be used as your boundary condition(s).

 

[72630]

Thanks cowski, but I need to put a fan inside my volume of air, becouse what I am trying to see is how the air-intake, placed in the bike, works with a suction behind at differents speed, using inlet/outlet fan to introduce the differents speeds for each case.