ВИЗНАЧЕННЯ НАДІЙНОСТІ ТЕПЛОПОСТАЧАННЯ ЖИТЛОВОГО МАСИВУ НА ОСНОВІ СИСТЕМНОГО МАТЕМАТИЧНОГО МОДЕЛЮВАННЯ ТЕПЛОВОЇ МЕРЕЖІ

The heat supply system of a residential estate of a large city is considered. The boiler room is located more than 70 m above the ground level of the residential neighborhood. A lowering pumping station is provided between the boiler room and the neighborhood. The project provided for technological protection of the pipelines of the heat networks of consumers of the lower zone from an unacceptable increase in pressure in them as a result of the de-energizing (stopping) of the network pumps of the pumping station. During emergency interruptions in the power supply of the pumping station during the heating season, water hammer and damage to the heat networks periodically occur, as well as forced interruptions in the heat supply of consumers, therefore, the analysis of the system's operability and reliability is an actual task. A heat supply system is a network consisting of directed flows, nodes where they converge and diverge, sources (sinks) of mass, heat, pressure, hydrostatic head, and pumping and heat-consuming equipment with their own characteristics. Heat supply or removal can be distributed (along edges (flows) or pointwise at nodes. Flows can change their direction depending on the pressure drop. For such a complex network topology, methods of discrete mathematics and graph theory are used. An improved mathematical model is presented, which consists of two graphs: hydraulic and heat, which are interconnected and are separate stages of calculation. The heat model takes into account the operational characteristics of heat consumption and heat losses in networks, and the hydraulic model takes into account the operational characteristics of superchargers and pipelines. The operational characteristics of the equipment and events that will affect the reliability and operability of the system are determined. An analysis of the thermal hydraulic regime of the heat network in abnormal operation options is performed and conclusions are drawn about the operability of the system.