Study on the frequency feature of acoustic leak signal in cast iron water distribution pipes

This paper investigates the frequency content of the leak signal in cast iron pipelines and the variation of the frequency content with leak rate. In order to pinpoint the location of suspected leak, the cross-correlation method is generally used, to estimate the time delay between two sensors which are positioned on two sides of the suspected leak position. The cross-correlation method has been adopted to study the spectra of leak signals in pipes of several sizes and at different propagation distances. The influence of pipe joint on the frequency content is also analyzed. The information related to the leak acoustic signal will help in the designing of appropriate procedures, and prompt the study in the generation mechanism and other characteristics of the leak signal.