Author(s): Petra A. Lopez-Jimenez; J. Jesus Mora-Rodriguez; Vicente S. Fuertes-Miquel; Carlos A. Platero-Gaona
Linked Author(s): Vicente S. Fuertes-Miquel
Keywords: No Keywords
Abstract: Water distribution networks are not completely safe: infrastructure systems may be old and deteriorated. This situation causes defects in pipes. Some operations done by network staff allow the entry of external fluids across these defects. This phenomenon, called pathogen intrusion, can cause a serious pollution problem on the network. This situation is especially important during hydraulic pressure transients, resulting in high and low pressure waves through the network. While high-pressures cause volume losses in the networks, there is evidence that intrusion of contaminants into the drinking water pipes occurs during the low-pressure episodes. In this contribution, we address the problem of contaminated water intrusion and backflow into the distribution network, by means of numerical modeling of the transient event, and also modeling the volume introduced in a pipe across failures. Numerical and experimental models were combined for this purpose: On one hand, Dyagats, computational model designed for determining the water hammer across water distribution pipes, it is used for determining the flow and pressure in pipes during the transient event. On the other hand, the relationship between pressure inside the pipe and the volume introduced across the defect, this relation comes from the experimental and numerical modelling obtained on previous researches done by the authors, based on physical models and numerical techniques of Computational Fluid Dynamics (CFD). As a consequence, we present a methodology to estimate the final external fluid introduced in a pipe during a transient event, depending on the defect characteristics and pressure development in the water distribution system.
Year: 2010