Pressure-Driven Demand Extension for EPANET (EPANETpdd)

Abstract

Introduction Predominantly, Demand-Driven hydraulic simulators such as EPANET used in optimization processes are configured to deliver water even when there is insufficient pressure to do so – Demand-Driven network solver (as EPANET – Rossman, 2000). In the analysis of structurally inadequate systems, however, recent studies [Germanopoulos, 1985, Hayuti & Burrows, 2004, Soares et al., 2003], have highlighted limitations related to the use of such demand-driven solvers. Initially, the sole requirement for the PDD extension was for it to be able to determine more accurately the non-revenue water unsupplied in a pressure-deficient network in order to better estimate the network’s Economic Level of Reliability [Tricarico et al., 2006]. A logical extension of that work required that the PDD simulator should also be able to operate in an EPS mode. As well as EPS, the application of the simulator to the Neptune project introduced two further requirements. PD demand nodes need to be able to exist in parallel with EPANET’s conventional emitters and the ability to specify emitter exponents on an individual rather than global basis. This functionality is required to simulate bursts in networks: PDD nodes will be used to observe the effects on demand nodes whilst EPANET’s standard emitters will be used to simulate unconstrained bursts, which will be represented by different emitter characteristics.