声强法在磁悬浮列车车厢声源识别中的应用

介绍了声强法中P—P技术的使用,并讨论了在使用P—P技术进行声强测量时的相位匹配问题。利用声强法对磁悬浮列车行驶时车厢内的声源进行了识别,并从频率响应的角度对分析结果进行了判断。可以得出,磁悬浮列车以430 km／h速度行驶时,噪声主要通过车厢壁面传入车内。研究了各声强测点处1／3倍频程频谱,分析了各测点处辐射声强对车内噪声频率成分的贡献。可以得出,车厢壁面在100 Hz以下的频率贡献较大,而其它频段上,各测点的贡献相当。

APPLICATION OF SOUND INTENSITY TECHNIQUE IN IDENTIFY THE NOISE SOURCES OF MAGLEV TRAIN

The P-P technique in measuring the sound intensity is presented and the phase should be matched when using the P-P technique to measure the sound intensity. The noise sources of the running maglev train compartment are identified by using the sound intensity method. The results are studied by analyzing the transfer functions. We can drawn a condusion that when the train is running at the speed of 430km/h, the noise transmits into the compartment mainly from the wall of the train. The 1/3-octave spectrums of the sound intensity are studied and the contributions of frequency component from every measuring point are analyzed. It can be concluded that the reflective intensity below 100Hz is mainly from the wall of the train. In other spectrums, the contributions of the three points are similar.