Numerical Study on the Noise Behavior of Vertical Axis WindTurbines

Vertical axis wind turbines are used for generatingelectricity from small Wind potentials. The main problem of theseturbines is noise pollution especially when they are installed nearresidential areas. In the present work, the noise of an H-Darrieuswind turbine is studied and the interaction of blades in noisegeneration and also the effect of observer position on noisereception are investigated. For this purpose, first noise sources aredefined by computational fluid dynamics, and then, FfowcsWilliams-Hawkings equation is applied for calculation the noise.The results of directivity calculation show that the noise receivedto observers is significantly dependent to observer angle.Moreover, although the blades have phase difference, theinteraction of blades amplifies the noise. Finally, the frequencydistribution is obtained by using Fast Fourier Transform. Theresults show that the highest peak is at third blade passingfrequency.

Keywords:

aerodynamics , CFD , noise pollution , wind turbine