轮轨噪声预测模型研究进展

从轮对振动声辐射预测模型、轨道结构振动声辐射预测模型与轮轨相互作用预测模型等方面，总结了轮轨噪声预测模型的研究进展，阐述了主要的建模方法及其特点，给出了一些典型结果，并提出了需要进一步研究的问题。研究结果表明:在建立轮对在给定简谐轮轨力作用下的振动声辐射预测模型时，可以将轮对简化为轴对称弹性体，轮对的振动响应通过一个2维的结构有限元模型来预测，而它的声辐射则通过一个2维的声学边界元模型来确定，这样的建模方法可以全面且方便地考虑轮对旋转所带来的陀螺效应和移动荷载效应；在建立轨道结构在给定的简谐轮轨力作用下的振动声辐射预测模型时，可以将轨道结构简化为无限长周期结构，轨道结构的振动响应通过周期结构理论来分析，而它的声辐射则应用2.5维声学边界元来预测，这样的建模方法可以方便地考虑轮轨力沿轨道的高速移动并大大简化声辐射的计算；在建立轮轨相互作用预测模型时，可以利用轮对和钢轨在轮轨接触点处的频率响应函数或脉冲响应函数，这样的建模方法只以轮轨力为未知量，不但使得相应的微分方程或积分方程未知量少，而且完全考虑了轮对的旋转及沿轨道的移动；轮轨噪声预测还需研究的问题包括高速列车轮对的声辐射、高速轨道相对车体的声辐射、地下铁路轮轨噪声，以及包含降噪措施的轮轨噪声预测模型等。 

Research progress on wheel-rail noise prediction models

The research progress on wheel-rail noise prediction models was summarized, the main modeling methods and their features were elucidated, and some representative results, and present problems that require further investigation were provided from several perspectives such as vibration and acoustic radiation prediction models for wheelsets and rail structures as well as wheel-rail interaction prediction models. Analysis research results show that for establishing a vibration and acoustic radiation prediction model for a wheelset under the action of a given harmonic wheel-rail force, the wheelset can be simplified to an axially symmetric elastic body, its vibration response can be predicted by using a 2D structural finite element model, and its acoustic radiation can be determined by using a 2D acoustic boundary element model. This modeling method allows a comprehensive and easy consideration of the gyroscopic and moving-load effects caused by the rotation of the wheelset. For establishing a vibration and acoustic radiation prediction model for a rail structure under the action of a given harmonic wheel-rail force, the rail structure can be simplified to an infinitely long periodic structure, its vibration response can be analyzed based on the theory of periodic structures, and its acoustic radiation can be predicted by using a 2.5D acoustic boundary element. This modeling method allows an easy consideration of the high-speed movement of the wheel-rail force along the rail and significantly simplifies the acoustic-radiation calculation. For establishing a wheel-rail interaction prediction model, the frequency or impulse response function at the contact point between the wheelset and steel rail is used. With the wheel-rail force as the only unknown, this modeling method not only allows a small number of unknowns in the corresponding differential or integral equation, but completely accounts for the rotation of the wheelset and its movement along the rail. Further research is required for solving problems involved in wheel-rail noise prediction, including the acoustic radiation from high-speed train wheelsets, the acoustic radiation from high-speed rails relative to the vehicle body, wheel-rail noise in underground railways, and wheel-rail noise prediction models that include noise-reduction measures. 11 figs, 113 refs.