Influence of Blade Tip Structure Change on Aerodynamic Noise of Wind Turbine under Yaw

In order to study the influence of blade tip structure change on aerodynamic noise of wind turbine under yaw, unmodified blade and double fork blade tip structure were studied 0=60° blade is simulated under the yaw angle of 0, 5, 15 and 30 respectively. The results show that the surface noise of both blades decreases with the increase of yaw angle. Compared with the unmodified blade, the variation range of blade surface noise with double fork tip structure is smaller. Under any yaw condition, the surface noise of the double fork modified blade is smaller than that of the unmodified blade, which is reduced by 1.6%, 1.4%, 1.7% and 0.09% respectively under the above four working conditions. This result provides a new idea for the low noise design of wind turbine blades.