Propagation of wind turbine noise through wakes and turbulent atmosphere

It is well known that the atmospheric inhomogeneities have great impact on sound propagation over long ranges. For the application of predicting wind turbine noise, either the flow wakes generated by rotating turbine blades or small-scale atmospheric turbulence can affect the propagation of sound over ground surfaces from individual turbines. In this thesis, the effects of wake and atmospheric turbulence on the propagation of wind turbine noise are investigated. By introducing the Parabolic Equation (PE) method, the effects of atmospheric changes in sound speed can be incorporated at each marching step as the prediction of sound field advances in the horizontal ranges. With a simulated wake profile near the wind turbine, more accurate predictions in the sound field can be achieved for realistic atmospheric conditions. This work aims to improve current prediction schemes for assessing the impact of wind turbine noise on the neighborhood communities