测量点位置对声源识别的影响

EFFECT OF MEASUREMENT POINTS DISTRIBUTION ON SOUND SOURCE IDENTIFICATION

振动表面的振速可以用声辐射模态展开表示,讨论了利用声辐射模态进行噪声源识别的方法。对于声源振速重建,关键就是确定展开系数。在声场中选择N个测量点,测量声场中的信息,求解展开系数。以平板振动为实例,利用声辐射模态对平板表面的振速分布进行重构,研究声源识别问题。通过模拟计算,发现声辐射模态方法结合Tik-honov正则化方法可以进行噪声源识别。同时就同一测量面上测量点的不同分布情况对识别的不同效果进行分析。研究结果表明:测量点位置分布不均匀时,声源识别效果较好。

The sound source surface velocity can be expressed in terms of the acoustic radiation modes. On this basis, an acoustic radiation modal method is introduced to identify the sound source. For reconstruction of sound source surface velocity, the key is to determine the expansion coefficients, which can be estimated by measuring the acoustic informations a N measurement points in the acoustic field. Taking the radiation of plate as an example the plate surface velocity is reconstructed according to acoustic radiation modes.The numerical simulation results show that the sound source surface velocity can be effectively identified by the acoustic radiation modal method combining with the Tikhonov regularization. The results from different distributions of measurement points are analyzed. As the measurement points are distrubuted asymmetrically, the result would be satisfactory.