Effect of rotational harmonics on sound power from HAWT blades

With rising greenhouse gas emissions and increasing energy demands across the globe, sustainable energy production has become essential today. Even though wind turbines help mitigate the harmful emissions, the HAWT blades are one of the key sources of aerodynamic noise and are designed to provide long term energy production. In this work we demonstrate the impact of rotational harmonics, turbine tilt angle on sound power level from HAWT blades during operation. At mean wind speed of 8 m/s the change in downward tilt angle of more than 5 deg increases the sound power level by 5 dB. Predominant noise occurred mainly from trailing edge regions of blade which suggests that number of blades in turbine, wind velocity profile and position of tilt angle significantly influenced on sound power level from wind turbine blades.