【作者】 王威；

【导师】 邹平华；

【作者基本信息】 哈尔滨工业大学 ， 供热、供燃气、通风及空调工程， 2008， 博士

【摘要】 供热管网可靠性评价是一个涉及概率论、随机过程理论和决策论等交叉学科的课题。供热系统的失效表象对于不同的管网形式和规模不尽相同,系统的失效及其元件失效模式的辨识和分析都十分困难。随着集中供热事业的日趋成熟,建立供热管网综合可靠性评价体系及高可靠度的大型供热管网设计模式是目前迫切需要解决的具有重要前瞻意义和经济价值的预研性应用课题,具有长远的社会经济效益和广泛的应用前景。本文通过建立完善的可靠性指标评价体系提升大型集中供热管网的设计理念。本文在前苏联热网可靠性研究的基础上,提出了管网可靠性指标体系;在分析热网元部件之间的逻辑关系的基础上,结合算例管网,研究了枝状管网和环状管网故障分析当量区的划分原则及可靠性指标的计算方法;结合事故关阀软件编制了HeatNetCAD程序,通过二次开发工具ObjectARX开发了通过AutoCAD界面输入管网的功能,使HeatNetCAD程序在AutoCAD环境中即可完成管网设计、分析、优化、形成或更新数据库的全部工程需求。结合热网故障发生的特点,分析了现阶段各城市故障维修水平的差异,提出以不同管道规格的故障修复时间区间作为热网可靠性计算的基础;根据间断(限额)供热房间的温降模型,以三面外墙的算例居住建筑单元为对象,计算了不同室外温度区间几种典型住宅建筑的建筑物热储备系数,给出了不同室外温度区间围护结构的热储备系数较小值;提出了无备用枝状管网可靠性约束条件,给出了代表城市满足可靠性约束条件的无备用枝状管网规模以及根据概率分析理论提出了无备用支线的最远输送距离的计算方法。提出了备用结构管网可靠性约束条件;给出了满足可靠性要求的限额供热系数的推荐标准;推导了由换热器换热的间接连接系统限额流量系数和限额供热系数间的关系式,论证了以限额流量系数和限额供热系数两个角度进行管网可靠性设计的思想;结合算例管网,分析了单连通管和双连通管管网结构在限额供热工况下的水力工况;推导了三管制热网供热系统限额流量系数与管网结构的关系式;用算例管网分析了三管制热网供热系统的应用并对比分析了本文提出的管线功能整体改变三管制结构与前苏联管线功能局部改变三管制热网供热系统的结构的优缺点;对分段阀的合理设置提出了依据;分析了环型管网环的数量的合理设置问题。随着热网技术的发展,特别是大规模的多热源环状管网的广泛应用,使热网的可靠性理论实践日益受到重视,可靠性评价和其它技术经济指标一样,将成为评价系统优劣的重要指标。本文旨在满足系统技术可靠基础上寻求最佳的优化设计方案,形成完整的供热管网可靠性理论及可靠性评价指标为迅速发展和壮大的集中供热提供设计依据。更多还原

【Abstract】 The evaluation of heat-supply network based on reliability is a crossed subject task, which involved probability theory, stochastic process theory and decision-making theory. The invalidation phan of heating system presents a perplexing evolvement process differ from the network form and its scale. It is hard to analyze and distinguish the failure pattern of components during its disabled process. With the centralized heating system becoming more mature, the foundation of synthetic reliability evaluating system and design mode of large-scale heat-supply network with high reliability are in advance application project provided with important portentous signification and economic values which cry for being solved. Thus it also possesses long-term social-economic benefits and far-ranging application foreground. By establishing a whole reliability index evaluating system, this paper promotes the optimal design method of large-scale centralized heat-supply system.Based on study of reliability related to heat-supply network in Russia, this paper establishes the reliability index system. Combining with the calculating pipe network, a reliability computing method of heat-supply network and the partition principle of equivalent zone of tree-shaped network and ring-shaped network are advanced by analyzing the logical relationship of its components. Associating with the software of valves shutoff under accident state, this paper writes a reliability index computing program—HeatNetCAD, which can be operated in Autocad environment tools by using secondary development tools--ObjectARX. The HeatNetCAD program can achieve the function of design, analysis, optimization and data update.According to the characteristic of failure occurring at heat-supply network, the diversity of different city on failure repairing level is analyzed, and the method of using failure repairing time zone for different pipe diameter as a foundation of reliability calculation of heat-supply network is presented, either. Based on the indoor air temperature drop model of being interrupted room or limited-heating supply room, the building heat-storage coefficient under different outside temperature zone are calculated by using calculating residential unit of three side of outerwall as object, and the heat-storage coefficient recommended value for several typical building configuration are brought forth. This paper also advances the reliability restricted terms of the size of satisfying reliability restriction under different outside temperature together with the allowable distance of non-spare tree-shaped heat-supply network. The reliability restriction of spare structure network and the recommended criterion of limited-heating coefficient satisfied reliability requirement in China are put forward. The relationship between limited-heating coefficient and limited-flux coefficient and the supply temperature of first network of indirect connecting system with interchanger is deducted. This function can be used to as a theoretical foundation of spare transportation design. The hydraulic results of spare structure with single connecting pipe and double connecting pipes of calculating pipe network under limited-heating supply state are analyzed. Moreover, the function of limited-flux coefficient and network configuration on three-pipe network is derived. The hydraulic analyses of calculating three-pipe network under normal state and limited-heating supply state are investigated. Comparing with another form of three-pipe network presented by scholars in Russia, the applications of three-pipe network are recommended by analyzing the calculating network and actual project. Some conclusion about reasonable setting of subsection valves and suitable loop size of ring-shaped network are presented, either.Along with the development of heat-supply network technology, especially the abroad application of large-scale ring-shaped pipe network with multi-heat source, the reliability theory of heat-supply network is attaching progressively importance to be carried out. The reliability evaluation becomes more important index on judging a system excellence like other techno-economic index. This paper aims to seek the optimal design scheme based on satisfying technique reliability of the system and form integrated reliability theory and evaluating index, in order to provide designing reference for rapidly developed centralized heat-supply project.更多还原