Hydraulic Transient Guidelines for Protecting Water Distribution Systems

Abstract

Transients can introduce large pressure forces and rapid fluid accelerations into a water distribution system. These disturbances may result in pump and device failures, system fatigue or pipe ruptures, and even the backflow/intrusion of dirty water. Many transient events can lead to water column separation, which can result in catastrophic pipeline failures. Thus, transient events cause health risks and can lead to increased leakage or decreased reliability. Transient flow simulation has become an essential requirement for ensuring safety and the safe operation of drinking water distribution systems. This article provides a basic understanding of the physical phenomena and context of transient conditions, presents practical guidelines for their suppression and control, and compares the formulation and computational performance of widely used hydraulic transient simulation schemes. Such capabilities greatly enhance the ability of water utilities to conceive and evaluate cost-effective and reliable water supply protection and management strategies and safeguard public health. lthough transient flow is initially a challenging topic, most people have some first-hand experience with " water hammer " effects. A common example is the banging or hammering noise that is sometimes heard when a water faucet in a house is rapidly closed. Although great complexity sometimes arises, the mechanism in this simple example typifies all pipeline transients. The rapid closing of a valve converts the kinetic energy carried by the fluid into strain energy in the pipe walls, causing a " pulse wave " of abnormal pressure to travel from the disturbance into the pipe system. The hammering sound that is sometimes heard indicates that a portion of the fluid's original kinetic energy is converted not only into pressure but also into an acoustic form. This acoustic energy, as well as other energy losses (including fluid friction), causes the transient pressure waves to gradually decay until new steady pressures and velocities are again established. Transient analysis of the performance of piping systems is often at least as important as the analysis of the steady-state operating conditions engineers usually use as the basis for system design. The total force acting within a pipe is obtained by summing the steady-state and transient pressures in the line. Tran

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Cite this paper

@inproceedings{Boulos2005HydraulicTG, title={Hydraulic Transient Guidelines for Protecting Water Distribution Systems}, author={Paul F. Boulos and Bryan W. Karney and Srinivasa Lingireddy}, year={2005} }