The Reliability Analysis Of Tree-shaped Heat-supply Network

With the improvement of people’s living level, the central heating system hasbecome an important infrastructure in a city. The central heating system with thecharacteristics of heating quality, environmental protection and energy conservation,has been rapidly developed and widely used in the world. Along with the heat-supplynetwork into the growth of service life and the continuous expansion of the scale, theprobability of failure in the improvement of heat-supply network, the system running isreliable or not directly affect people’s lives and production. Therefore, how to improvethe network reliability, ensure the heating quality, reduce the accident of the network,has become an important problem of reliability research.After expounding the definition of heat-supply network reliability and the relatedconcepts of heat-supply network fault and accident, this paper combines the idea ofprobability theory to analysis the related basic parameters of network reliability. Anddiscuss the statistical and computational method of failure parameters(mainly refers tothe failure parameters of pipes and valves), the computational method of low loadequivalent of the tree-shaped heat-supply network, and the divided method of failureanalysis equivalent area.This paper also deduces the calculation formula of tree-shaped heat-supplynetwork reliability index, and summarizes the calculation steps of tree-shapedheat-supply network reliability index. According to this formula to calculate thereliability evaluation index of the eastern new district heating system of Handan City.When this paper discussed in the determining metheod of fault pipeline repair timeand the computational method of room cooling time, it detailed introduces thecalculation formula of room heat capacity and room heat reserve coefficient.Taking atypical room in Handan for example, it calculates the cooling time of this room. Baseson the data and combines with the fault pipeline repair time to determine the allowedvalue of tree-shaped heat-supply network maximum diameter in Handan. It alsoanalyses the influence of tree-shaped heat-supply network trunk length on systemreliability.Finally, this paper puts forward relevant measures to improve the tree-shapedheat-supply network reliability. Mainly include: increasing the pipeline number of the heat source export; reasonable setting the segmented valve, drain valve and vent valve;improving the quality of components, and shortening the repair time; strengtheningthe operation management; using the system structure with spare capacity.