中文摘要：

针对压力管道泄漏声发射信号的含有高频噪声、多模态以及频散现象,影响对泄漏源定位精度的问题。研究了一种基于Gabor小波变换与小波包熵值降噪相结合的方法对泄漏源进行定位。首先对采集的泄漏信号进行小波包熵值降噪以滤除背景噪声,其次对降噪后的信号进行Gabor小波变换获得其在特定频率下的时间-频率空间分布,确定不同模态信号到达同一个传感器的时间差,并结合压力管道的频散曲线特性确定该频率下不同模态的群速度,最终实现对管道泄漏源的精确定位。

英文摘要：

Considering the phenomenons of high-frequency noise,modal and dispersion in the acoustic emission signals of the pressure pipeline leak which affects seriously the localization accuracy of the leakage source,based on the Gabor wavelet transform and the theory of modal acoustic emission,this paper presented a method to locate leakage source of pressure pipeline.Firstly,the wavelet packet entropy was used to filter out the background noise. Secondly,the Gabor wavelet transform was applied to get the time-frequency spatial distribution of the signal after noise reduction to determine the time difference of the different modals arriving at the same sensor and the group velocity of different modals which determined by the dispersion curve of the pressure pipe. And ultimately the precise location of the pipeline leakage source was gotten.