Simple question about a Rotating Wall
 

Hello, imagine a hollow cylinder (3D), the outer wall is stationary and the inner wall is rotating, my question is: Is that the only information that fluent needs?? It just need to set up that the inner wall is rotating about an axis, do I have to use MRF for this? I am not 100% how this works so any reference material will be appreciated.

You can use either SRF or MRF for this purpose. In both approaches, the walls are stationary and the fluid between them rotates. Have a look at the SRF and MRE pertinent concepts in fluent user guide. By the way, fluent tutorial regarding granular Eulerian model is a stirred tank which can help you to handle your problem as well. Have a look at it too.

I am doing some minors experiments, and yes, I just need to say that the wall is moving, It recognizes that the fluid volume must move with the wall, thanks anyway for your answer