closed casing with fan and water

Tom

Hy, I try to simulate water in a cylindrical casing (free surface, diameter 1m, high about 0.2m) and a propeller with a diameter of 0.05m in the water. The sense of that is to bring the water into rotation with a given speed v-tan at special points. The propeller is modelled as a fan with no circumferential and radial velocity-component. I use tets, k-eps. Now the circumferential-velocity of the water in the casing is at all points of the simulation as double as high as the measured one (0.3m/s). yplus at the side walls and the bottom is ok, the surface on the top is symmetrie (no shear-stress..). What can I do ? Thank you very much