Implementing MRF with rotor
 

Hi All,

I am trying to implement multiple reference frame on a rotor in a cylinder problem (a reactor).

I hope I can get some clarification on how to create the mesh and define the boundary conditions between the rotating and stationary zones. The rotating zone should encompass the rotor, and the stationary zone is outside the rotating zone.

For the rotating zone mesh, do I create a cylindrical mesh without excluding the rotor and its shaft volume? And for the stationary zone, do I create a cylindrical mesh excluding the rotating zone volume?

As for the boundary conditions, do I set the interface between the rotating and stationary zones as cyclicAMI? And for the impeller and its shaft as rotating wall velocity (not sure whether fixed value or rotating wall velocity)?

Thank you for your help.

Best Regards,
Kevin

Hi Kevin,

this I just answered in an old thread:

Maybe my (second?) answer is of any help to you? In short: I prefer to create a blockMesh and devide the parts via sHM with an stl cylinder for the moving domain, then adapt the boundary, dynamicMeshDict and b.c. files.

I also strongly recommend to have a look at the tutorial cases first (I admit, sometimes the right one is hard to find, but "find" and "grep" can be powerful friends here). For your case there are several ones in:

$FOAM_TUTORIALS/incompressible/pimpleDyMFoam/

(from what I know they use a slightly different approach than I do to create the mesh)

Edit:

Sorry, I mixed MRF with sliding meshes. So forget my text above. I am just leaving it for reference. However, this might be of some help. From what I get, it is one mesh with different cell zones. Did you take a look at the simpleFoam tutorials?

Hi Henning,

Thanks for your link to the presentation, but I have looked at it already and still need some clarification on how to define my boundaries, especially at the interface between rotating zone and stationary zone and whether I need to apply cyclicAMI. Thanks

Kevin

Ok, I have not worked with MRF so I can really help you there. Have you tried to search the tutorial cases with:

grep -rn '$FOAM_TUTORIALS' -e "MRF"

or any other keywork that fits better than MRF?