Modeling leakage reduction through pressure control

摘要

Pressure control can be an effective way to reduce leakage in water distribution systems. In this article, the authors present results from an experimental study conducted to determine an appropriate equation to define the flow from leaks. The orifice flow equation is most appropriate in situations in which the dimensionless orifice/soil number—an indicator of head loss caused by orifice losses versus porous media (soil) losses—is large, as it is in most water distribution systems. This finding indicates that flow emitters are an appropriate method to model leaks. The authors also describe the application of computer modeling in a real-world distribution system and demonstrate how a model can be used to evaluate pressure settings and estimate leak reduction and possible pressure problems. Pressure reduction is most effective when both leakage and pressure are relatively high, flow is controlled by a pressure-reducing valve or variable-speed pump, and the terrain is relatively flat. However, as discussed in this article, time-of-day control may be needed for pressure contral to work.