400 km/h高速列车车下带格栅裙板区域气动噪声机理及影响因素分析  

Analysis of aerodynamic noise mechanism and influencing factors at the skirt with grille under the vehicle at 400 km/h

作　　者：张宗发 肖新标[1] 韩健 杨益 ZHANG Zongfa;XIAO Xinbiao;HAN Jian;YANG Yi(State Key Laboratory of Rail Transit Vehicle System,Southwest Jiaotong University,Chengdu 610031,China;School of Mechanical Engineering,Southwest Jiaotong University,Chengdu 610031,China)

机构地区：[1]西南交通大学轨道交通运载系统全国重点实验室,成都610031 [2]西南交通大学机械工程学院,成都610031

出　　处：《实验流体力学》2024年第1期79-90,共12页Journal of Experiments in Fluid Mechanics

基　　金：国家自然科学基金项目(U1934203)。

摘　　要：位于高速列车车体下部区域的通风口格栅与设备舱壁面构成格栅–空腔结构,列车高速运行时,该结构的流声耦合问题较为突出,有必要深入分析其流声耦合机理。将位于车体下部区域的带格栅裙板简化为带格栅的二维空腔模型(格栅–空腔结构),采用延迟分离涡数值模型(Delayed Detached Eddy Simulation,DDES)研究其气动噪声产生机理、流场和声场特性等。研究结果表明:当列车以400 km/h速度运行时,格栅–空腔结构开口处的剪切振荡较为剧烈,特别是空腔冲击边缘附近区域;基于总声压级的空间、频域分布和湍流压力波数–频率谱,发现形格栅–空腔结构的流场始终处于自激振荡的过渡状态,且各位置的总声压级和波数域上的振荡幅值始终低于V形格栅–空腔结构和半圆环形格栅–空腔结构;对目前常用的半圆环形带格栅裙板考虑通风口的出风作用后,观察到空腔内部的涡团演化明显减缓,直接导致格栅附近的总声压级大幅下降约15 d B,表明出风作用能够显著降低带裙板格栅的近场噪声。The grille located in the lower part of the train body is usually easy to form a grille-cavity structure with the equipment bay’s surface.The problem of flow-acoustic coupling resonance of this structure is more prominent when the train runs at high speed.It is necessary to further analyze the flow-acoustic coupling mechanism of the structure.Therefore,the skirt plate with the grille,which is located in the lower part of the train body and can be simplified to a grilling-cavity structure,is taken as an example.And the Delayed Detached Eddy Simulation(DDES)is used to analyze the grille-cavity structure’s aerodynamic noise generation mechanism,flow field,and sound field.The results show that the shear oscillation at the opening of the grille-cavity structure is more intense when the train is running at 400 km/h,especially near the impact edge of the cavity.From the spatial and frequency domain distribution of the global sound pressure level and the wave number spectrum of the turbulent pressure,it is found that the flow field of the square grille-cavity is always in a transition state of self-excited oscillation and the amplitude of oscillation in the global sound pressure level and wave number domain at different positions is always lower than that of the V-shaped and semi-circular grille-cavity.Considering the effect of the air outlet on the semi-circular grille cavity currently used,it is observed that the evolution of vortex clusters inside the cavity slows down significantly,which directly causes the global sound pressure level near the grille to drop by about 15 dB.It can be considered that the effect of air outlet has a significant effect on the reduction of near-field noise of the skirt plate with the grille.

关 键 词：高速列车 流声耦合 格栅 裙板 剪切振荡 格栅–空腔 总声压级 气动噪声 

分 类 号：U271.9[机械工程—车辆工程]