Author(s): Alireza Keramat, Mohamed S. Ghidaoui, Xun Wang
Linked Author(s): Alireza Keramat
Keywords: Leak detection, inverse problem, water hammer, noise, matched filter
Abstract: This paper addresses leak detection in the presence of measurement noise using inverse transient analysis in the time domain. The unknown leak parameters are determined by optimizing a merit function, which fits the numerically modeled pressures to measured pressures. As a result of measurement noise, the estimated parameters may correspond to some fictitious leaks whose computed pressure head best matches the noisy measurement not leak reflections. This issue is demonstrated in this research and a merit function to decline it is suggested. It is based on maximizing the signal-to-noise ratio (SNR), which is usually termed as Matched Filter in literature. This function is then compared with the conventional least square objective function and its properties subject to noise are assessed. It is found that the performance of each merit function mostly depends on the variance of noise and the system properties, which may change from case to case. It is advised to use both merit functions for localization separately and then the more reliable result corresponds to that of the objective function with lower variance
Year: 2017