Fan in a housing
 

Hi,

I'm new with Ansys CFX and want to simulate a fan, embedded in a complex geometry. The fan itself I have already simulated. But if I want to simulate the total situation, then only a small area have to rotate. I will use ICEM as meshing tool. Do I have to define the rotational region already in my CAD file, or can I define it as a part or a region in ICEM ? Or is there a totally different way ?

Thanks, Holger