供水管网全网关阀预案与关键阀门分析

Analysis of valve closing schemes and key valves in water distribution networks

研究供水管网全网关阀预案一次性生成方法并评估阀门和管线的重要性,可为实施管网快速抢修和增强管网可靠性奠定技术基础.为此,应用图论传递闭包理论和Warshall算法计算识别管网子区(关闭阀门隔离事故管线后形成的管网最小隔离区域)和多余阀门,建立阀门-管网子区拓扑模型.然后应用该模型分析管网隔离子区的关联子区(阀门关闭后下游关联影响停水区域)及其非必关阀门(下游阀门),生成面向单事故点和多事故点的供水管网全网关阀预案,进一步分析了阀门失灵后的拓展关阀方案;以用户缺水量(位于事故子区及其关联子区)为指标评估管网子区和阀门重要性,识别关键子区(管线)和关键阀门,辅助管网科学巡检与阀门养护,提高阀门可靠性.天津市供水管网实际应用表明,管网子区为全网关阀预案制定及阀门与管线重要性分析提供了捷径.

To support rapid repair of pipe accidents and improve the reliability of water distribution networks（ WDNs）,an approach of finding all valve closing schemes for a network in one time and evaluating the importance of valves and pipes was studied. By using graph theory and Warshall Algorithm（ WA）,redundant valves which cannot block the flow of water and segments（ i.e. the smallest isolation portion of water supply networks formed by closing a subset of valves） were identified to build valve-segment models. Using the models,unnecessary closing valves（ downstream valves of isolated segments） and unintended segments which are parts of the network disconnected from water source（ s） as the secondary effect of segment isolation were then analyzed. After excluding the unnecessary closing valves from the boundary valves of isolated segments,all valve closing schemes were formed which can meet a single or multiple pipe accidents. Also,the extension of valve closing schemes was analyzed when a valve malfunction occurs. Additionally,to improve the reliability of valves and assist scientific pipe patrol and valve maintenance,the importance of segments（ pipes） and valves was evaluated by using the total demand shortfall coming from isolated segments and their unintended segments while key valves and segments were identified. The application in Tianjin water networks illustrates that segments provide a shortcut to build all valve closing schemes and analyze the importance of pipes and valves for WDNs.