关键词: 风力发电机, 自通风, 直接冷却, 气动噪声, 仿真, 1 / 3 倍频程

Abstract: To study the spectral distribution characteristics of aerodynamic noise of self ventilated and direct cooling wind turbines, a hybrid computational aerodynamic acoustics method was used to simulate the aerodynamic noise of self ventilated and direct cooling wind turbines. The flow rate, noise sound pressure level, and one-third octave band of the motor at rated speed were tested. Through simulation and experimental comparison, the flow simulation error was 4. 25%,
and the average sound pressure level simulation error was 2. 4 dB ( A) , which verifies the reliability of the simulation method. The frequency spectrum distribution characteristics of motor noise in the 1 / 3 octave band were analyzed, and the direction of noise reduction was pointed out.

Key words: wind turbine, self ventilated, direct cooling, aerodynamic noise, simulation, 1 / 3 octave band