02. Industrial Aerodynamics

We propose a prediction method for aerodynamic noise that does not depend on the specific design parameters of the impeller, and discuss the performance of its broadband noise generated from a stall-controlled wind turbine. A comparison of the noise characteristics of the two types of wind turbines indicated that narrowband noise of the turbines was generated by the Karman vortex street shed from the blade element at the blade tip. Moreover, the predicted noise spectra indicated that these vortices were difficult to form at the wind speed under stall control, whereas the wind speed after stall control increased the broadband noise owing to the high relative velocity by the separated flow.