基于匹配场处理法的管道局部阻塞定位方法

Discrete blockage localization using the matched-field processing method

水锤波管道管内湍流及用户取水极易产生噪声,且噪声声波与阻塞反射波高度相似,严重干扰传统方法的定位结果.鉴于此,本研究在频域内严格推导了阻塞的水锤波解耦模型,并提出了基于全波形反演的新型阻塞定位方法,其鲁棒性表现为:能够在噪声环境中(信噪比低至-10 dB)精准定位单个阻塞;如果两个相邻阻塞的间距大于最小检测半波长,那么新型方法能够较准确地估计它们的位置;当管道中的波速存在不确定性时,新型方法仍能准确定位阻塞;与传统定位方法相比,新型方法抗噪声干扰能力更强,所需的信号带宽更窄.

The transient wave-based method for discrete blockage localization in water pipes is accurate,efficient,and nondestructive.However,turbulent flows and customer consumption may generate ambient noise,which is highly similar to the blockage-induced reflections;thus,seriously reducing the localization accuracy of the traditional method.In this regard,the factorized transient wave model for a blockage was derived analytically and a novel blockage localization method based on the full waveform inversion was proposed.This method can accurately localize a single blockage even if the signal-to-noise ratio is as low as-10 dB.Moreover,if the distance between two adjacent blockages is greater than the minimum detection half-wavelength,the proposed method also gives good estimations of their locations.When the wave speed of the pipe is uncertain,the proposed method can still localize the blockage accurately.Compared with the traditional method,the proposed method is more accurate and robust against ambient noise.