moving refernce frame (MRF) vs sling mesh
 

Dear All,

I am working on the modeling of flow field in stirred tanks currently. The geometry consists of impeller, baffle, etc. I have tried both moving reference frame (MRF) for steady state and sliding mesh (SM) for transient simulation. I have a few questions to ask you guys.

1. I noticed some post (http://www.cfd-online.com/Forums/flu...nce-frame.html) in this forum said MRF is not good and yields wrong simulation result. Is this confirmed by many Fluent users?.

2. Some guy said “steady-state” can be reached in some stirred tanks after many cycles to reach by sliding mesh method. What does “steady-state” mean? Do it mean that flow field will be the “same” when impeller is located in the same position in the next cycle?

3. Will initial condition in transient case affect the final simulation result if the so-called "steady state" can be reached after many cycles? Or it affects the convergence speed only?

Please help. Any comment is really appreciated. Thanks again!