全封闭设备舱对隧道内160 km/h地铁气动声源影响

Influence of Fully Enclosed Equipment Cabin on Aeroacoustic Source of a 160 km/h Metro in Tunnel

随着地铁列车速度提升至160 km/h,隧道环境下地铁列车表面气动激励显著增强。应用大涡模拟对隧道内160 km/h地铁列车脉动流场结构和表面气动噪声源进行数值仿真,定量评估全封闭设备舱设计对地铁列车气动声学性能的优化效果。结果表明:全封闭设备舱设计能够疏导车底气流,使车底气流更多集中在转向架舱两侧溢出,同时引起车下主要涡结构尺度增大。对应的,列车整车车体气动噪声源能量减小约2.9%;其中头车、中车1分别增大5.7%和9.4%,中车2和尾车分别减小4.2%和13.8%,各节车体声源能量分布更加均匀;列车高频声源能量减小,整车800 Hz峰值频谱能量减小约4.0%。研究成果将为160 km/h地铁列车气动降噪设计提供参考。

With the speed of new generation metro trains raise up to 160 km/h,the aerodynamic excitation on metro trains surface aggrandized significantly in tunnel environment.Large Eddy Simulation is used to simulate the pulsating flow field structure and surface aerodynamic noise source of 160 km/h metro trains in tunnel,and the optimization effect of fully enclosed equipment cabin design on the aeroacoustic performance of metro train is evaluated quantitatively.The results show that the fully enclosed equipment cabin design can dredge the air flow under the train,the air flow under the train concentrated and overflow on both sides of the bogie cabin.Meanwhile,the scale of the main vortex structure under the vehicle is increased.Correspondingly,the aerodynamic noise source energy of the whole train is reduced by about 2.9%.In which,the head car and the mid-car 1 increased by 5.7%and 9.4%respectively,while the mid-car 2 and tail car decreased by 4.2%and 13.8%respectively,and the sound source energy distribution on each car body is more even.The high-frequency sound source energy of the whole train is reduced,and the peak spectrum energy of the 800 Hz of the whole vehicle lessened by about 4.0%.The results of this paper will provide a reference for the aerodynamic noise reduction design of 160 km/h metro trains.