Aerodynamic and Noise Characteristics Analysis of Large Wind Turbines

In order to investigate the aerodynamic and noise characteristics of large wind turbines, the NREL 5MW wind turbine was selected as the study object. Initially, the SST k-ω model was employed to calculate the flow field, and after the flow field stabilized, the FW-H equation was used to solve the sound field. The simulation results indicated that negative pressure regions exist on the pressure side of the blade, with pressure decreasing and then increasing as the blade span increases. The vorticity in the wake region near the rotor center is relatively high, gradually decreasing and diffusing with the increase in axial distance. In the near-wake region, the sound pressure level (SPL) at the blade root varies significantly with axial distance, whereas the SPL from the mid-blade to the blade tip shows less variation, consistent with the wind speed variation in the near-wake region. In the far-wake region, the SPL generally increases with the blade span. The A-weighted noise energy is primarily concentrated in the mid-to-high frequency range.