A numerical study of the acoustic radiation characteristics of the aerodynamic noise in the near-wake region of a wind turbine

We use the acoustic source integral plane defined by the Kirchhoff-Ffowcs-Williams-Hawkings equation to develop the radiation characteristics of the acoustic wave and collect sound field data for the flow field in the wake of a rotor to determine the optimal attack angle of the incoming flow. The distribution and propagation of acoustic radiation in the wake of the rotor and the acoustic radiation characteristics of the inter-influenced noise are also investigated. Simulation results suggest that the noise radiation in the near-wake region of the rotor strongly influences the section's central, central eddy, and tip eddy regions. Further exploration of the motion trails show that in the central eddy region, the peaks of acoustic pressure levels migrate toward the center with increased tip speed, whereas in the tip eddy region, they migrate outwards. These results provide theoretical references for the design of high-efficiency, low-noise, horizontal-axis rotors for wind turbines.