_RL ArDudrFac
ArDudrFac = vfFacMom*1.
ArDudrFac = 0.
& +( fVrDw(i,j) - fVrUp(i,j) )*rkSign*ArDudrFac
fVerUkp(i,j) = ArDudrFac*vrF(i,j)