[killer2234]

Dear all:
I am using swak4Foam utilities--vectorSwakSetValue to set up with a fixed normal velocity from porous cylinder's surface in a still air surroundings.

below part is specified in the fvOptions file.

porousFaceNormalVelocity
{
    type vectorSwakSetValue;
    active true;
    timeStart 0;
    duration 100;
    vectorSwakSetValueCoeffs
    {
        selectionMode cellSet;
        cellSet  c0;

        variables (
                "xp=0.5;"
                "yp=0.5;"
                "up=50;"
                "x=pos().x;"
                "y=pos().y;"
                "rp=sqrt(pow((x-xp),2)+pow((y-yp),2));"
        );
        useMaskExpression false;

        expressions {
            U "vector(up*(x-xp)/rp,up*(y-yp)/rp,0)" [0 1 -1 0 0 0 0];
        }
   }
}

Now comes my question: it seems that the velocity field didn't changed so much. I have double check with my cellSet and it was correct. And the solvers runs without error:

Selecting finite volume options model type vectorExplicitSetValue
    Source: momentumSource
    - selecting cells using cellSet c0
    - selected 1600 cell(s) with volume 0.04

I have also tried to specify with the faceSet which contains the surface part , but I still get similar results as before
.
Is there anything wrong with my settings? Or how can I specify an surface-normal velocity on an cylindrical surface.

Great thanks for giving me any suggestion!!

[killer2234]

Could anyone give me some hint, please