Leakages and pressure relation: an experimental research

Abstract

Abstract. Leaks in water systems are presently a frequent and increasing event that involves cost increase and poor service, not compliant to quality standards and modern management criteria. The most recent data available in Italy, resumed into the report issued by Control Committee for Water Resources Use (CONVIRI), shows leakages with an average value of 37 %. It is therefore important, for maintenance perspective, to investigate occurrence and evolution of water leaks and the analytical link between leaks Q p and network pressure P, for a reliable calibration of water networks quali-quantitative simulation models. The present work reports the first results of an experimental campaign started at Laboratory of Hydraulics of Department of Hydraulics, Geotechnical and Environmental Engineering of University of Naples Federico II in order to analyze the features of Q p (P) relation, which are compared with other results issued in literature.

Effect of hydraulic and geometric factors upon leakage flow rate in pressurized pipes

“…When leakage area increased, leakage flow rate also increased. This result is consistent with that reported by Greyvenstein (2007), Walski et al (2009), andPaola &Giugni (2012). Reducing the leakage area by half (from 100 to 50 mm 2 ) reduces leakage flowrate by 47%.…”

Experimental and Numerical Assessment of Water Leakages in a PVC-A Pipe

“…Most of the research studies carried out so far have addressed the characterization of the parameters of the leakage laws for different pipe materials and shapes and sizes of the cracks [10][11][12][13][14][15]. Specifically, it has been observed that the coefficient C of Equation (2) increases almost linearly with the area of the crack, which is consistent with the other reported formulations.…”

“…Nevertheless, Franchini and Lanza [16] pointed out that the significant deviations of N from the theoretical value may be basically ascribed to the improper quantification of the leakage coefficient C. Through a dimensionless analysis, the authors emphasized the effectiveness of the Torricelli's equation in describing the pressure-leakage relationship and proposed that the influence of hydraulic factors and of the local deformability of the leak area is explained through the correction of the product C L A L by means of a multiplicative factor. De Paola and Giugni [14] carried out an experimental comparison between steel and ductile iron pipes considering orifices with different shape and size. Both static and dynamic operations were simulated, pointing out how the emitter coefficient C strictly depends on the orifice size, whereas the leakage exponent N tends to a value close to the theoretical one of 0.50.…”

Experimental study of crack behavior in pressurized high-density polyethylene water pipes

“…Despite lots of studies on the leakage in pipes, few studies have been conducted on the plastic pipes especially HDPE. The leakage exponent for the longitudinal slits covers a wide range (0.48≤ N ≤ 1.97) and pipe material has a significant impact on the amount of N [6,[23], [24], [25]]. The leakage exponent of longitudinal slits in plastic pipes is higher than other material [[26], [27], [28]].…”