Help with boundary conditions

Dan

I am simulating the flow around a wind turbine rotor, but my simulation is not converging to a value of 1E-05. In the residuals window the minimum value I can get is 1E-03 and it converged to tha value very slow. I was wondering if somebody can give me any advice about the boundary conditions that I am using. I have specified inlet velocity boundary conditions with a value of x=0 , y=0, z=4 ( z corresponds to the rotation axis of the wind turbine), do I need to specify velocity values for the x and y components?, the outlet is a pressure boundary condition of 101325 Pa, I realize as well that I should set the boundaries conditions a bit further than they actually are, anyone with a good recomendation?. I am using a rotating grid for the fluid domain near the blade and the rest of the domain is stationary respect to the rotating frame.

Steady-steady incompressible flow -Inflow boundary velocity specified cylindrical V= 4m/s -Outflow Boundary condition average pressure specified P=101325 -Wall smooth boundary condition applied to the blade wall -Free-slip boundary conditions -Opening Boundary condition P=101325

Figures of the boundary conditiond and grid are in the links below

http://members.lycos.co.uk/iigp/hpbimg/untitled.jpg

http://members.lycos.co.uk/iigp/hpbimg/untitled2.jpg