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Hi Folks,

I have a question regarding dynamic parts. I try to simulate the effect of different rotation speeds on particle laden flows. For that I want to rotate a goeometry (here a Rotor called Dynamic) and I think that a MRF is the best (?) for these kinds of problems.

Now I have included the MRF setting in snappyHexMesh

Code:

refinementSurfaces

    {

        Dynamic        //3

        {

            // Surface-wise min and max refinement level

            level (5 6);

        }

     Nacelle_simple_lang    //4

        {

            // Surface-wise min and max refinement level

            level (5 6);

        }

    refinementCylinder

    {

        level (2 2);

        faceZone MRF;

        cellZone MRF;

        cellZoneInside inside;

    }

in /system/fvOptions

Code:

MRF

{

    type                   MRFSource;

    active                 true;

    selectionMode    cellZone;

    cellZone             MRF;



    MRFSourceCoeffs

    {

        origin    (0 0 0);

        axis      (1 0 0);

        omega     100; 

    }

}

and also in /system/topoSetDict

Code:

actions

(

    {

        name    MRF;

        type    cellZoneSet;

        action  new;

        source  zoneToCell;

        sourceInfo

        {

            name MRF;

        }

    }

);

But I have no idea if all setting are correct or not.

I also get this message

Code:

--> FOAM FATAL ERROR: 

Cannot find cellZone refinementCylinder

Valid cellZones are 1(MRF)



    From function option::setCellIds()

    in file fvOptions/fvOption.C at line 158.



FOAM exiting

Where is the mistake?

One other point is the following:
Are the origin coordinates (here in red) the coordinates relative to your rotating frame?

MRFSourceCoeffs
{
origin (0 0 0);

All help is welcome.

Andreas