Dear all,
First of all, thank you very much for the opportunity to be a member of this forum.
I want to calculate the steady state response of the rotor of the NREL 5 MW wind turbine under steady and uniform wind conditions (almost the same as that performed for the land-based turbine in nrel.gov/docs/fy09osti/38060.pdf except that I neglect the tower and nacelle effect) using the standalone AeroDyn software based on BEM method. In this regard, I have used the data available in the just mentioned PDF in order to validate my results, including the thrust, torque and power coefficients (although a small difference between the results is expected as I am ignoring the tower and nacelle effects, together with the structural deflections).
Accordingly, I have the following two questions, which I would be so grateful if someone could answer:
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Is it possible to calculate the steady rotor rotational speed through performing a steady state simulation of an initially stationary rotor where a uniform wind is blown upon it? If yes, what changes are needed to be done in the input/driver files?
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To perform an initial validation of my results, I have used the normalized values of RotThrust, RotPwr and RotTorq given in the above-mentioned PDF. However, I have noticed that the normalization of the RotThrust using the maximum thrust force available in the wind (1/2air densitywind speed^2rotor sweep area) results in the thrust coefficient values larger than one for wind speeds smaller than roughly 7 m/s (you can see the normalized values in the excel file attached). Could you please check if I am using a correct equation (1/2air densitywind speed^2rotor sweep area) for the normalization of the thrust force or there is something that I am not taking into account?
Thrust.xlsx (11.7 KB)