An introduction to the assessment of reliability of the heat supply systems

The considering of the issue of heat supply system reliability requires taking into consideration their complexity and the extent of realization. Two approaches to reliability assessment for heat supply systems are possible: a simple global approach and universal system approach. The global approach is based on analysis of information related to system operation as a whole. The system approach induces system decomposition and combining partial models fro-selected components. This approach considers specific features and structure of heat supply system and diversified reliability criteria for selected subsystems. Methods for system evaluation of heat supply system reliability depend on number of parameters used for system description. The one-parameter assessment is based on so called stationary readiness coefficient for the whole system. In two-parameter method an additional parameter is added, named as mean failure period or as mean system capacity period. In three-parameter method, the generalized reliability characteristic based on mean heat shortage is added to give more information about the system.