boundary conditions for a rotating wind turbine problem
 

Hey all,
I have been trying to simulate a rotating wind turbine but with the bc's I have , I constatnly get a reversed flow at the exit and an incresing turbulent viscosity ratio. I got rid of the viscosity ratio error by refining my mesh and reducing the length scales but it doesnot seem to change the issue with the reversed flow. My bc's are:
Velocity Inlet at inlet
VElocity Inlet at PFF
Pressure Outlet at exit
Blade surface has no slip condition
The left and right walls of the doamin have periodicity.

Need some help with this problem asap!