Hello Retsam and thank you for your help.
I read the guide you published and I would like to ask you for some clarification concerning the blades. If I understood correctly, the blades are cylindrical holes in the cylinder that represents the pipe, is that right? Are they like hollow cylinders in the pipe cylinder?
I think I understood the CFD part but the CAD part is not perfectly clear to me.
Again, thanks a lot for your help.