城市燃气输配管网可靠性的多视角分析

Mufti-perspective Analysis on Reliability of Urban Gas Transmission and Distribution Network

以可靠性为切入点,对城市燃气输配管网进行多视角分析,阐述管道结构可靠性、管网连通可靠性、管网水力工况和供气可靠性等相关问题的区别与联系,明确不同角度的可靠性分析是遵循了不同的途径进行的,应视不同类型的生命线工程系统与研究目的而有所侧重。管道结构可靠性及连通可靠性是从机械角度对管网系统及组成单元进行分析,侧重考察组成管网的各部分及管网系统在一定条件下具有结构完整性的概率,而未考虑水力工况的影响。管网水力工况分析是从流体力学角度分析管网各节点压力、流量的整体工作状况,其侧重点是在个别管道失效情况下,管网还能够在多大程度上满足各类用户的用气需求,水力工况分析未考虑结构失效概率的影响。管网供气可靠性是在考虑结构可靠性和水力工况的基础上采用的一个综合评价标准,是一种概率意义上的对管网整体供气能力的综合评价,根据这种评价结果,可以从管道结构和水力工况两个方面来引导改善设计或改进已建成系统,进而更好地促进管网供气功能的发挥。

Taking the reliability as the starting point,the urban gas transmission and distribution network is analyzed from multiple perspectives,and the differences and relations of related issues such as the reliability of pipeline structure,the reliability of network connection,the hydraulic working conditions of the network and the reliability of gas supply are expounded. It is clear that the reliability analysis from different angles is carried out in different ways,and should be focused on different types of lifeline engineering systems and research purposes. The reliability of pipeline structure and the connection reliability are to analyze the network system and its constituent units from the mechanical point of view,and focus on investigating the probability that each part of the pipe network and the pipe network system have structural integrity under certain conditions,without considering the influence of hydraulic condition. The hydraulic working condition analysis of the network is to analyze the overall working conditions of pressure and flow of each node of the network from the perspective of fluid mechanics. The emphasis is on the extent to which the network can still meet the gas demand of various users under the condition of individual pipeline failure,and the influence of structural failure probability is not considered in the hydraulic working condition analysis.The gas supply reliability of the pipe network is a comprehensive evaluation standard adopted on the basis of considering the structural reliability and hydraulic working conditions. It is a probabilistic comprehensive evaluation of the overall gas supply capacity of the pipe network. According to the results of this evaluation,it can be guided to improve the design or improve the built system from the two aspects of pipeline structure and hydraulic working conditions,so as to better promote the gas supply function of the pipeline network.