ABSTRACT
ABSTRACT: Leakage from water and sewerage pipelines is a major problem worldwide. Recently, methods to detect leaks using fluid transients have been developed and tested using laboratory data. Wang et al. (2002) have derived a method based on the damping rates of different Fourier modes of head versus time traces; hereafter referred to as the damping rate method. This method neglects unsteady friction, assumes a small magnitude, impulsive transient, and was experimentally verified for small values of Reynolds number only. These assumptions are highly restrictive, and would be difficult to satisfy in practice. This paper investigates the accuracy of the damping rate method under (i) transients generated by flow perturbations of different magnitudes and different time scales, and (ii) different Reynolds number. This involves performing numerical experiments with a quasi-two-dimensional (2D) transient flow model. It is found that the accuracy of the damping rate method provides good results, even for large Reynolds number, provided the timescale of the initial transient disturbance is short, or the magnitude of transient perturbations are small.
