power curve of windmills with CFD

sayid

Dear users,

I am currently working on my thesis about estimating power curve of a 3 bladed HAWT at the university using FLUENT. But, there are problems with the problem setup and the results .

Since I need multiple points of power obtained from 1 blade (I will multiply by 3 because of the periodic modeling), I use multiple reference frames model and spalart allmaras turbulence model. I define constant angular velocity to the fluid domain, absolute angular velocity of 0 rad/s for the wall domain surrounding the fluid domain and the turbine blade. (reference:fan tutorial) And I change inlet velocity of air and expect to find the power from moment*angular velocity. There is a certain characteristic form of the power curve where the curve has a peak and falls. But using this model, the power values I find are all unrealistic values, exceeding the power available in the wind which is already known.

My question is should I subtract the moment for the case of same angular velocity and zero inlet velocity condition from all of my cases. Because if I do this I get better results. Or is it totally wrong?