基于瞬态边界元法的铁路车轮声辐射研究

轨道车轮的振动声辐射瞬态特性分析能够直观反映车轮结构的时域振动响应和时域声辐射特性.利用有限元/瞬态边界元法的计算机仿真技术,对S形辐板车轮在时域下进行振动及声辐射特性分析.研究结果表明:踏面和辐板的轴向位移响应级基本一致,且轮辋和辐板之间轴向振动存在耦合关系;踏面、轮辋和辐板轴向位移响应级的变化趋势一致,具有类似于"拍"的周期特性;在车轮轴线上距离车轮30m处的声压集中在60~80dB,且随时间的增加整体缓慢上升,再趋于平稳;声压主要分布在3 500Hz以下的频段.研究结果为瞬态声辐射仿真技术在车轮振动声辐射特性研究中的应用提供参考.

Characteristics Analysis of Sound Radiation of the Railway Wheel Based on Transient Boundary Element Method

The noise radiation of the wheel is one of the main sources of wheel/rail noise.Time domain characteristic analysis of vibration and sound radiation of the railway wheel can reflect its transient characteristics of vibration response and sound radiation.By the computer simulation of finite element method and acoustic transient boundary element method,the time domain characteristics analysis of vibration and sound radiation of the railway wheel with S-shaped web plate are carried out.The results show that,axial displacement responses of the tread and the web are approximately in the same level,and there is a close coupling relationship between rim and web;the axial displacement responses of the tread,the rim and the web have the same tendency which has a periodic behavior similar to beat vibration;the sound pressure at the field point,30 m distance from the wheel in axis,concentrates in the range of 60 ~ 80 dB,and with the time increase,it has a general tendency that increasing slowly and then tending to steady;with the change of time, sound pressure frequencies concentrate below 3500Hz,and above 3 500 Hz they are little.It provides references for the application of transient acoustic radiation simulation technology used in the study on radiation characteristics of vibration and sound of wheels.