Accurate Detection and Localization of Water Pipe Leaks through Model-Based TDR Inversion

Abstract

The problem of water scarcity affects many areas of the world due to water mismanagement and overconsumption and, more recently, to climate change. Monitoring the integrity of distribution systems is, therefore, increasingly important to avoid the waste of clean water. This paper presents a new signal processing technique for enhancing the performance of the methodology of leak detection in water distribution pipes based on time domain reflectometry (TDR). The new technique is based on a particular kind of TDR inversion (spatial TDR) based on a “gray-box” lumped parameter model of the system. The model does not include, e.g., radiative phenomena, non-TEM (transverse electromagnetic) modes etc. but is capable of reproducing accurately the complicated reflectograms obtained by a TDR leak detection system assuming a proper profile of capacitance per unit length along the sensing element. Even more importantly, the model is identified using only the reflectograms taken by the system with very little prior information about the system components. The developed technique is able to estimate with good accuracy, from reflectograms with unclear or ambiguous interpretation, the position and the extension of a region where water is located. The measurement is obtained without prior electromagnetic characterization of the TDR system components and without the need of modeling or quantifying a number of electromagnetic effects typical of on-site measurements.

Multi-Leakage Source Localization of Safety Valve Based on Uniform Circular AE Array and Improved MUSIC Algorithm

“…Some scholars use signal processing technology to denoise the collected signals or use adaptive elimination to improve the positioning accuracy of the time reversal location algorithm. This method is suitable for linear sensor arrays and is not suitable for safety-valve-leak location [10,11]. The positioning method combining the cross-time spectrum (CTFS), hyperbolic positioning algorithm, and acoustic emission sensor array has been proposed to locate large-scale pressure and long-distance pipeline leakage, but the denoising processing of the collected signal is not considered, resulting in the positioning accuracy not reaching the range within 3% [12][13][14][15].…”