大型风力机气动噪声仿真与分析

以2 MW风力机为研究对象,用Pro/E进行三维建模,用Fluent对其流场和声场进行仿真分析。采用大涡模拟(LES)模型求解风力机流场非定常流动,获得流场漩涡强度和流线,采用FW-H声学模型计算气动噪声。结果表明,由叶根至叶尖漩涡强度和声压脉动逐渐加强,在叶尖区域达到最大值,叶尖区域是风力机噪声主要来源,叶片背风面漩涡强度和声压脉动比迎风面高,导致距风力机相同距离的背风面合成声压级高于迎风面,塔影效应是风力机气动噪声重要组成部分,气动噪声主要是中低频噪声。

Simulation and Analysis of Aerodynamic Noise ofa Large Wind Turbine

The wind turbine with 2MW power was regarded as research object. The three-dimensional model was established by Pro/E. The flow field and sound field of the turbine was simulated by Fluent. The intensity of vortex and streamlines information was obtained while the unsteady flows within the flow field of wind turbine were solved by the Large Eddy Simulation(LES). At last, the aerodynamic noise was calculated by F-WH acoustic model. The results show that the vortex intensity and sound pressure pulsation gradually strengthen from the root to the tip, and reach maximum at the tip of turbine. The tip region is the main source of noise. The leeward of rotor have the stronger vortex intensity and sound pressure pulsation than windward. It cause synthetic sound power level of leeward was higher than that of windward, while the leeward and windward of rotor are the same distance from the wind turbine. Tower-shadow effect is an important part of the aerodynamic noise, and the aerodynamic noise is mainly middle and low frequency noise.