vortexSource
{
    type swakTopoSources;

    active true;
    timeStart 0;
    duration 1e7;
    selectionMode cellZone;
	cellZone	vortexZone;

    vectorSwakImplicitSourceCoeffs {
	switchExplicitImplicit true;
        variables (
            "xMin=min(pos().x);"
            "xMax=max(pos().x);"
            "yMin=min(pos().y);"
            "yMax=max(pos().y);"
            "zMin=min(pos().z);"
            "zMax=max(pos().z);"
			//Burgers vortex analytical expression 2D
			"alpha=1;"
			"r=mag(pow(xMax/2,2)+pow(zMax/2,2));"
			"vr=-0.5*alpha*r;"
			"vz=alpha*r;"


        );

        expressions {
				   "vector(vr,vr,vz)*normal()"
		}
        dimensions [0 1 -1 0 0 0 0];
    }