[Mitpostdoc]

Hello there,
since the last week I have been struggling with the grid of a centrifugal compressor. I have been asked to mesh it with a structured mesh and for a single impeller-return channel passage and run the simulation in Fluent.
Unfortunately, I am having a very hard time with ICEM... I tried to break down my difficulties in few questions:

1) Periodic boundaries:

- I must manually define the planes for the periodic boundaries. Unfortunately, if I use the Mesh>Global Mesh parameters> Set up periodicity of ICEM the program does not understand the geometry. The Impeller blades are bending backwards and ICEM does not "see" that. I had to manually create the periodic planes and move the blocks vertices one by one. Is there any other more clever way to do that?

- Multiple periodicity. This is probably the worse limitation. I can specify only 1 rotational angle of periodicity . However, the impeller and the return vanes have a different angle. I do not see any solution . Any idea how to solve it ?

2)Sliding mesh:

- I can not see any reference in the ICEM manual to sliding/rotating interfaces. I did not find anything in the tutorial either. How does it work?

Finally, Icem is crashing every 5 minutes. That happens if I delete a block and I try to undo, or simply while I am rotating the view. Is that normal?

Thanks you