高速列车动车转向架气动噪声数值分析

为研究高速列车动车转向架气动噪声特性，建立了动车转向架空气动力学模型，采用定常RNGk-湍流模型与宽频带噪声源模型对其气动噪声声源进行初步探讨，并结合非定常LES大涡模拟与Lighthill声学比拟理论进行了远场气动噪声分析。研究结果表明:动车转向架气动噪声源为轮对、构架、牵引电机1、枕梁、垂向减振器、抗侧滚扭杆等结构的迎风侧凸起部位，且构架对动车转向架远场气动噪声的贡献最大，其次为轮对和抗侧滚扭杆，然后为垂向减振器和枕梁，牵引电机1、牵引电机2、空气弹簧和横向减振器对远场气动噪声的贡献较小。动车转向架远场气动噪声是宽频噪声，具有衰减特性、幅值特性和气动噪声指向性。在低频部分能量较大，中心频率为25、50Hz，且分布规律不随运行速度的改变而变化。 

Numerical Analysis of Aerodynamic Noise of Motor Car Bogie for High-Speed Trains

In order to study the aerodynamic noise characteristics of motor car bogie in high-speed trains, an aerodynamic model of motor car bogie was established, a preliminary study on the aerodynamic noise source of the motor car bogie was made using the steady-state RNG k- turbulence model and the broadband noise source model, and the far-field aerodynamic noise was analyzed by combined use of the transient-state large eddy simulation (LES) and Lighthill' s acoustic analogue theory. The results show that the wheel set, bogie frame, traction motor-1, bolster, vertical shock absorber, anti-rolling torsion bar and other protruding parts on the windward side are the aerodynamic noise source of the bogie. Among them, bogie frame has the largest contribution to the total far-field aerodynamic noise of the bogie, the wheel set and anti-rolling torsion bar have the secondary contribution, and the vertical shock absorber and bolster have the third contribution amount. Compared to the above components, the traction motor-1, traction motor-2, air spring and lateral shock absorber have less contribution to the total noise. In addition, the far-field noise of the motor car bogie is a broadband noise, characterized by attenuation, amplitude and aerodynamic noise directivity. The main energy of the noise in the low frequency band is concentrated at the centre frequencies 25 and 50 Hz, and the power spectral density distribution does not change with the train speed.