【作者】 何忠华；

【导师】 袁一星；

【作者基本信息】 哈尔滨工业大学 ， 土木工程， 2014， 博士

【摘要】 城市供水管网是城市重要的基础设施，担负着从水源向千家万户保持不间断输水的重任，任何导致用户停水或不能及时获得所需水量水压的事故，都将对正常的社会生产和生活造成巨大的影响。研究并改善供水管网的可靠性，有效保障用户对水量水压的需求，对于提高供水企业的经济及社会效益具有重要的现实意义。本文以城市供水管网的可靠性为研究内容，建立了供水管网物理模型，然后基于物理模型研究了剩余能量熵作为供水管网可靠性指标的可行性、供水管网可靠性的影响因素和可靠性评价方法，为供水管网的设计、运行、诊断和维护提供依据。针对实际供水管网的隐蔽性以及直接进行实验操作的艰巨性和风险性，提出利用物理模型研究供水管网中的可靠性问题。在搭建供水管网物理模型的基础上，通过将物理模型中用户节点的结构设计成“压力变送器-电动球阀”的形式，实现了对用户所需水量的模拟；通过控制管段上球阀的开度，实现了对物理模型中管段海曾-威廉系数的模拟。将物理模型的试验运行数据与EPANET的水力模拟运行数据进行比较，表明物理模型试验能较好地反映管网水力工况，满足后续可靠性试验研究的精度要求。针对拓扑结构冗余度高且剩余供水能力分布均匀的供水管网在应对需水量增加、管段故障等事故方面能力强的特点，通过引入剩余能量因子表征管段的剩余供水能力并结合“熵”的理论，提出以剩余能量熵表征剩余能量因子在节点上游各管段间分布的均匀性，建立了供水管网剩余能量熵计算模型。依托物理模型工况试验对供水管网剩余能量熵作为可靠性度量指标的可行性进行了试验研究。通过采集相关工况数据，计算了供水管网在各管段断开工况下的剩余能量熵以及水量可靠度、水压可靠度、流量熵、恢复力指数和剩余能量因子等可靠性指标，通过与这些经典的供水管网可靠性指标进行比较，结果显示剩余能量熵与其它指标间均存在很好的正相关关系，证实了以剩余能量熵作为供水管网可靠性度量指标的可行性。供水管网常面临着节点需水量增加以及爆管等问题，从改善供水可靠性兼顾节能的角度出发，基于物理模型工况试验，分别研究了供水管网需水量增加导致可靠性降低的问题以及供水管网爆管并关阀后的优化调度问题，分别建立了基于用户节点地面标高的分区模型和以水泵运行频率为决策变量的多目标优化调度模型。将两个模型分别应用于物理模型试验中，结果证实了两种模型的可行性和有效性。基于“爆管区域-爆管后果”模式，建立了供水管网可靠性评价模型。该模型将管段发生爆管的随机性作为不确定性因素的来源，充分考虑了管段的可用度、用户需水量的时变性、供水管网中阀门的布置情况以及优化调度等影响可靠性的因素，能够更真实、准确和全面地反映供水管网可靠性。在爆管工况试验中，针对一一枚举供水管网中各管段及其组合的不可行性，提出基于供水管网阀门布置情况的区域划分法，依次对各区域内某根管段爆管导致该区域被隔离后的供水管网进行可靠性评价，大大降低了试验次数。更多还原

【Abstract】 Urban water distribution systems (WDS) are the critical infrastructures in city, which are responsible for delivering water to users all over the city uninterruptedly. Any failure that causes the users to fail to receive sufficient pressure and flow rate will have an enormous disaster impact on normal life and productive activities of the people. The research and improvement of reliability for WDS has positive realistic significance for ensuring daily water demand of users effectively and increasing the economic and social benefits of water utility. In this paper, water distribution systems reliability is mainly studied based on its physical model. And then the feasibility of surplus power entropy (SPE) being used as a reliability indicator, influencing factors and assessment methods of WDS reliability under various abnormal conditions are also studied to provide guidance for the design, operation, diagnosis and maintenance of a WDS.Firstly, the structure of user node in physical model is designed as “pressure meter–ball valve” pattern in order to simulate the water demand of user node. The Hazen-Williams coefficient C of pipe is simulated by controlling the opening of ball valve situated at corresponding pipe. By comparing the operating results between physical model and its simulation model by EPANET, the results indicates that the physical model experiment can simulate the hydraulic conditions of WDS effectively. And its experiment results can meet accuracy requirements of reliability experiment in this paper.Secondly, considering that the WDS with higher redundancy structure and equivalent surplus power factor among upper pipes has higher reliability under failure conditions (such as increasing water demand and pipe failures, etc.), surplus power entropy is introduced to describe the uniformity of surplus power factor among the upper pipes. While the surplus power factor describes the surplus water supply capability of pipe, entropy measures the uniformity of element distribution among upper pipes. An effective experimental study on SPE being as a reliability indicator is conducted by physical model experiment. A comparison between SPE and some classical reliability indicators is done by acquiring some related operating data and calculating these indicators under a range of failure conditions. These classical indicators include available water reliability, pressure reliability, flow entropy, resilience index and surplus power factor. The comparison results show a positive relationship between SPE and other reliability indicators, which confirms the feasibility of SPE being used as an indicator of capacity reliability.Thirdly, low reliability caused by increasing water demand and optimization scheduling after isolating the bursting pipe are studied based on physical model experiment from the viewpoint of improving reliability and reducing energy consumption. And then，the dividing district model based on node elevations and the multi-objective optimal scheduling model taken pump operation frequencies as decision variables are established and confirmed by physical model experiment. Finally, water distribution system reliability assessment model is establishedbased on “bursting area-consequences” pattern. This model takes the stochastic bursting of pipe as uncertainty factor sources and can reflect the reliability of WDS correctly because of considering some factors, such as the availability of pipe, variable water demand of users during a hydraulic operating cycle, layout of valve and optimization scheduling. In the bursting experiment, due to the infeasibility of enumerating failing pipe and their combinations one by one, a regional division method is proposed, based on the layout of valves. WDS is assessed after every district is isolated from the WDS one by one. This method greatly reduces the number of experiment.更多还原