Study on the mechanism of vibration signal generation in water supply pipeline leaks

Abstract

This study addresses water supply network leakage by employing numerical simulations to overcome challenges related to too small orifice hindering sensor deployment. Utilizing computational fluid dynamics and finite element methods, coupled with large eddy simulation, flow field distribution within pipes and at leakage orifice is investigated. The formation of leakage flow fields is categorized into three stages: leakage formation, unstable leakage, and stable leakage. During the leakage stage, the flow field is analyzed, and four regions—bottom central, bottom vortex, upper central, and upper vortex—are identified based on spatial characteristics. Detailed variable distribution patterns (velocity, pressure, vorticity) are provided in various planes. Understanding these distribution characteristics, six excitation sources responsible for generating leakage vibration signals are identified: pulsating velocity, pulsating pressure, bubble rupture, cavity pulsation, vortex-induced vibration, and gas expansion. The relationships among these excitation sources and their intensities concerning pipeline pressure and leak orifice radius are analyzed. Notably, a positive correlation between pressure and the intensity of all excitation sources is observed, while the impact of leak orifice size on these sources is found to be intricate. This research significantly contributes to an enhanced understanding of the physical processes associated with pipeline leakage.