[Daniel4]

hi guys
i have some problem setting up the boundary condition for my simulation.can you give me suggestions or guide me through it.

i want to simulate a fan and also a ducted fan. i imported the geometry and did the mesh.but how can i set the boundary condition so the fan can rotate at certain RPM.should i make the geometry as a big cylinder in CATIA(while creating the geometry of the fan) as for the velocity inlet and pressure outlet and etc?

how to do the MRF on this simulation?

attached is the geometry i imported and also the mesh of my geometry.

thanks

[Daniel4]

i tried to edit in 3D cad and do some sketches to make the boundary condition,but when i try to generate volume mesh,it says the surface is not closed.

but when i do a solid extrude,it will make my fan disappear.i just dont know what to do now.

anyone please help me or give me any suggestion!!

[Muzz]

There is a tutorial in the Star-CCM+ documentation which should help you with this particular problem. It deals with the operation of a marine prop in open water. You should be able to apply some of the same principles and it will also assist you with the MRF problems you're having.

If you're getting an error that states a surface is not "closed and manifold", it usually means that there are some issues with your imported CAD model, from my experience. You'll need to look into "surface repair" methods from the documentation as well.