EMU6动车组气动声学性能分析

Investigation on aeroacoustic performance of EMU6

采用三维、不可压缩和Lilly LES+FW-H方法,对1:8缩比3车编组EMU6动车组以200,250,300和350 km/h的车速运行时进行气动噪声特性数值模拟,得到列车不同速度级运行时的压力、速度与涡量分布,表面脉动压力、辐射声场等气动与声学性能。研究结果表明:偶极子声源强度主要分布在转向架及其周围的车体表面位置;A计权声压频谱在略小于1 000 Hz频率处测点声压级达到峰值;气动噪声分布频带很宽,噪声能量在1 000 Hz左右较为集中,往高频和低频部分则逐渐衰减;头车流线型附近声压级较大,在尾车以后越远离车体,声压级越小。其研究结果可为高速动车组的气动声学特性优化研究提供参考依据。

The paper studied the aeroacoustics performance of the Electric Multiple Units(EMU)6 with different running speeds from 200 km/h to 350 km/h.The 3D incompressible Lilly LES+FW-H method was adopted to investigate the distribution of the pressure,velocity and vorticity,the surface fluctuating pressure and the radiated sound field.The results show that the dipole source intensity is mainly distributed at the bogies and the surrounding train surface.The A-weighting sound pressure spectrum reaches the maximum at the frequency slightly lower than 1 000 Hz.The frequency band for the aerodynamic noise is wide,and the acoustic energy concentrates at the frequency around 1 000 Hz and decays with the increase and decrease of frequency.The sound pressure level(SPL)is high at the streamline of the leading car.The SPL at the wake of the train decreases with the increase of distance from the ending car.The above results may provide reference for the aeroacoustics optimization design of the EMU.