直埋热水供热管道泄漏定位检测实验研究
Experimental study on leak location detection of directly buried hot water heating pipeline
摘要：
选用傅里叶滤波法和小波阈值法进行了管道泄漏信号降噪和泄漏定位的对比研究。在DN300管路的实验直埋热水供热系统上进行了泄漏检测实验,采用小管径支管和调节阀模拟泄漏点、加速度传感器测量声波振动信号,依次选用2种滤波方法对直埋热水供热管道泄漏的声波振动信号进行数据降噪处理,讨论了泄漏信号降噪前后的信号频域特征和定位精度。在北京市某小区直埋供热管道进行了声波降噪泄漏检测工程验证,定位偏差不超过1.0 m。研究表明,傅里叶滤波法和小波阈值法对直埋热水供热管道泄漏定位的声波振动信号降噪处理效果显著,小波阈值法保持了全频段的信号特征,可获得更高的定位精度。
Abstract：
In this paper, the Fourier filtering method and wavelet threshold method are used to make a comparative study of signal noise reduction and leak location. The leak detection experiment is carried out on the directly buried hot water heating system of the DN300 pipeline. The small diameter branch pipe and the regulating valve are used to simulate the leak point, and the acceleration sensor is used to measure the acoustic vibration signal. Two filtering methods are selected successively to reduce the noise of acoustic vibration signal of the directly buried hot water heating pipeline leak. The frequency domain characteristics and the location accuracy of the leak signal before and after denoising are discussed. Acoustic noise reduction leak detection engineering verification is carried out in a directly buried heating pipeline in a residential area of Beijing, and the positioning deviation is less than 1.0 m. The results show that the Fourier filtering method and the wavelet threshold method have a remarkable effect on acoustic vibration signal noise reduction for leak location of the directly buried hot water heating pipeline. The wavelet threshold method keeps the signal characteristics of the whole band and can obtain higher positioning accuracy.
Keywords:directly buried heating pipeline; signal noise reduction; leak location detection; Fourier filtering method; wavelet threshold method; frequency domain; time domain