Physics-based synthesis of wind turbine noise

Overview & Synopsis

It is known that the wind turbine noise is a potential source of disturbance and annoyance for the people in the vicinity of the wind farms. The work presented in the thesis addressed the problem of wind turbine noise by developing a physic-based model to synthesize and study it. The synthesis model detailed here advances from the frequency-domain model for wind turbine noise developed by Tian and Cotté and revisits certain components in light of the recent literature. A synthesis tool is created to convert the frequency domain noise predictions to a time signal with the help of a window function. The designed window function is made to account for the difference in the propagation time observed due to the rotation of the blades.A few test cases of the synthesized sound can be found in the thesis for different scenarios. The model is finally compared to the field measurements done for an entire wind farm and show fairly good results for the source as well as the propagation part. The developed model is a useful tool which can be used for psychoacoutic evaluation to understand the perception and annoyance factor of wind turbine noise. Along with obtaining the spectral levels of the expected noise from the wind farm, the tool also produces audible signals that can be further used for the desired purpose. Thus making it a useful tool that abridges the gap between citizens, local authorities and acousticians.