Valve-Based Reliability Assessment for Water Distribution Systems

Abstract

Valve plays an important role in water supply networks when it needed portion isolation of the network to repair or rehabilitate broken components. To evaluate the valve-based reliability of water distribution system, the concept of “segment” is proposed. A segment is the cut set of pipes and nodes that bounded by valves, which is the minimum isolation unit when it is necessary to be shutdown during planned and unplanned maintenance. In this paper, the concept of reliability is defined as the ability of network to provide adequate demands to consumers within specified limits of pressure. Finding the optimal strategy of valve shutdown and assessing the reliability of the water distribution system are two main issues which this paper concerns. A segment and outage segment generation technology will be used to divide the entire system into multiple segments, which contains a portion of pipes and nodes. According to the given general statistics information of the segment, we can find an appropriate shutdown scheme and assess the reliability of the system. At the end of this paper, a case study is presented in which a Chinese city pipe network is analyzed and assessed, and an optimization scheme is proposed.