供热管网泄漏检测模型的建立与诊断

发布时间：2018-01-20 19:37

本文关键词： 供热管网瞬变流慢变流漏失检测贝叶斯(Bayes)方法　出处：《哈尔滨工业大学》2015年硕士论文　论文类型：学位论文

【摘要】：近年来,随着我国供热事业的不断发展,供热管网漏损控制已逐渐被重视起来。城市供热管网的漏损事故,不但造成经济损失,而且还严重影响了我国的民生工程。供热管网具有复杂的拓扑结构且处于地下管线空间,因此对于供热管网的漏损定位具有一定的难度。本文基于瞬变流理论,对供热管网中的易漏部件补偿器和阀门进行压力突变状态下的数学建模;同时基于慢变流理论,建立供热管网泄漏模型,然后通过引入系统辨识方法建立供热管网漏失检测模型,并对该模型进行理论上的研究。供热管网由很多元部件组成,其中的方形补偿器与阀门是两个重要的部件也是易漏部件。对方形补偿器根据局部阻力等效原理将其转化为缩管径的短管段进行模拟,观察其在压力突变状态下补偿器的压力波动;同时根据波的独立传播与叠加原理,研究阀门的特性,通过对比单阀调节与双阀调节时末端阀门以及中间阀门的压力变化,找到合理布置阀门的方式。最后对哈尔滨市某一供热管网的事故工况进行情景复现。根据图论理论知识,建立供热管网的拓扑结构,并以该结构作为泄漏模型的基础,建立供热管网的基本水力模型。将泄漏发生位置向最近的一个节点靠拢,使得泄漏量成为该节点流量的一部分,其中泄漏量采用孔口出流公式进行计算。根据矩阵论的知识导出以泄漏量为变量的各管段流量与节点压强,最后通过一个管网进行了该泄漏模型的水力计算。由于管网运行的状态会影响管网中管段流量和节点压强的大小,以此将这两个参数作为监测参数。在已有的供热管网泄漏模型基础上引入系统辨识理论,建立了基于贝叶斯(Bayes)方法的供热管网漏失检测模型。通过设置两种不同泄漏位置的方案对一供热管网进行验证运算,计算得到泄漏点的概率分别为0.738和0.852,能够很好的找到泄漏点的位置以及泄漏程度,从而验证了模型的可靠性。
[Abstract]:In recent years, with the continuous development of heating industry in China, leakage control of heating network has been gradually attached importance to. Leakage accidents of urban heating network not only cause economic losses. Heating network has complex topology and is in underground pipeline space, so it is difficult to locate the leakage of heating network. This paper is based on transient flow theory. The mathematical model of the leaky parts compensator and valve in the heating pipe network under the condition of sudden pressure change is carried out. At the same time, based on the theory of slow variable flow, the leakage model of heating network is established, and then the leakage detection model of heating network is established by introducing the system identification method. The model is theoretically studied. The heating network is composed of many components. Square compensator and valve are two important components and easy to leak. The square compensator is transformed into a short pipe with reduced diameter according to the principle of local resistance equivalence. The pressure fluctuation of compensator was observed under the condition of sudden change of pressure. At the same time, according to the principle of independent wave propagation and superposition, the characteristics of the valve are studied, and the pressure changes of the end valve and the middle valve are compared between the single valve regulation and the double valve regulation. Finally, the accident condition of a heating network in Harbin is reappeared. According to the theory of graph theory, the topological structure of heating network is established. Taking the structure as the basis of the leakage model, the basic hydraulic model of the heating network is established. The location of the leakage is close to the nearest node, which makes the leakage become a part of the node flow. According to the knowledge of matrix theory, the flow rate and node pressure of each section of the pipe with leakage volume as variable are derived. Finally, the hydraulic calculation of the leakage model is carried out through a pipe network. Because the state of the pipe network operation will affect the pipe flow and the pressure of the node in the pipe network. Taking these two parameters as monitoring parameters, the system identification theory is introduced on the basis of the existing leakage model of heating network. The leakage detection model of heating network based on Bayesian Bayes method is established, and the verification operation of a heating network is carried out by setting two different leakage locations. The probability of calculating the leakage point is 0.738 and 0.852respectively, which can find the location of the leak point and the leakage degree, which verifies the reliability of the model.
【学位授予单位】：哈尔滨工业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TU995.3

【参考文献】