Research On The Reliability Of Heat Source Based On Semi-markovian Method

With the development of centralized heating system, the foundation of reliability evaluating system for heat source is a serious problem which cries for being solved now. It has far-reaching significance and values in further development of the centralized heating system. The reliability study of the heat source involves probability theory, decision-making theory and the theory of stochastic processes, etc. In order to improve the heat source’s reliability of large-scale heating systems, this article points out the calculation of the heat source reliability index, and establishes a reliability evaluation system for heat source.This study is based on previous results in Russia and proposes the use of Semi-Markov method to study the reliability of the heat source to achieve the establishment of a heat source reliability theory system under this model and gain selected indexes which used to evaluate the reliability of heat source reliability. Then the results of the study are applied to calculate the three actual models to verify its correctness and practicability.In the establishing the theoretical system, combining probabilistic model and thermal physics, this article defines the basic concepts involved in reliability analysis of heat source, redefines the heat source failure, gives the classification of heat source failure, proposes the evaluation index of heat source reliability, gives the general principle of the theoretical system, and demonstrates the reliability index calculation for heating systems and unit components.In the application of theoretical system, this article presents the research ideas which divides heat source device into three models. According to the established theoretical system, we analyze each type of model, and gain reliability index calculation method for each model, including the initial data acquisition, semi-Markov process’ State diagram, transition probability calculation,and heat source reliability index calculation. The first model, mainly for boiler units, According to examples, analyzes the relationship between the boiler unit’s reliability indexes, and proposes reasonable basis for heat source unit selection. The second model, mainly for pumping equipment, combined with practical examples, analyzes the reliability of the pump. The third model, mainly for the coal ash removal system and boiler water treatment system, According to examples, analyzes the reliability of such components.At last, according to logical relationships between parts of a heat source system, the reliability of the source system is calculated.,making recommendations boiler unit selection aspects and reliability improvements from a heat source reliability point,providing an example of the actual source of the heating system reliability index calculation.With heating network constantly develops toward large-scale, centralized, heat source reliability evaluation will be an important indicator as evaluating the overall heating system. This article aims to establish a method to calculate the reliability of heat source and establish a complete theoretical system for heat source reliability.