I would like to know which is the most 'aerodynamically efficient' angle of mounting for the nacelle (horizontally) or the rotor with respect to the tower for upwind machines.
The reason I mentioned aerodynamically efficient because some turbine manufacture choose a certain angle to lean the rotor away from the tower to avoid strikes especially where the rotor is too close to the tower. For others, that may not pose a problem and they could go for the most efficient angle.
A few turbine manufacturers that I have spoken to say that 7 degrees inclination w.r.t the ground level is the most efficient one, since if it was 0 degrees, the rotor would be perfectly parallel to the tower and that may pose some turbulence in medium to high winds.
While a few others manufacturers consider that just an excuse to steer attention from a bad turbine design where the tip of the lower passing blades tends to be too close to pose a striking risk. In fact, any thing more than 0 degrees would tend to loose efficiency. That's a reason why some designs furl upwards in high winds to decrease efficiency and rpm.
I would like to get opinion from the community on the most efficient angle of inclination in their opinion.
Thanks.
he should combine questions or hire a consultant.
