基于Morlet小波分析的高速铁路轮轨粗糙度声学特征

Acoustic Characteristics of High Speed Railway Wheel⁃Rail Roughness Based on Morlet Wavelet Analysis

通过跟踪实测一动车组车轮旋修前后的粗糙度及其通过路基直线段、路基曲线段和桥梁区段3个典型区段的钢轨粗糙度并对数据进行曲率修正,研究高速铁路车轮和钢轨的粗糙度特征;通过测量3个典型区段动车组车外噪声并进行0~5000 Hz的Morlet小波分析,研究轮轨滚动瞬态接触下的声学非稳态特征。结果表明:车轮旋修前的17阶多边形特征和钢轨不平顺峰值波长在小波时频图中有较明显反映;车轮和钢轨特征波长的声学不平顺等级在车外噪声中有明显反映;从声学角度可以有效进行轮轨典型粗糙度特征的识别。

By tracking the measured roughness of EMU(Electric Multiple Units)wheels before and after the rotary repair and the rail roughness when EMU wheels passing through three typical sections such as the subgrade straight line section,subgrade curved section and bridge section,and correcting the curvature of the data,the roughness characteristics of wheel and rail of high speed railway were studied.Based on the measurement of the exterior noise of EMU in three typical sections and the Morlet wavelet analysis of 0~5000 Hz,the acoustic unsteady characteristics of wheel-rail rolling transient contact were studied.The test results show that the 17-order polygon features and the peak wavelength of rail irregularities before wheel rotary repair are obviously reflected in the wavelet time-frequency diagram,the acoustic irregularity level of characteristic wave length of wheel and rail is obviously reflected in the noise outside the train.From the acoustic point of view,the typical roughness characteristics of wheel and rail can be identified effectively.