Study on Standby Hydraulic of Single-heat-source Single-looped District Heating Network

Since the concept of reliability was put forward, how to improve the reliability of district heating system to effectively save energy and ensure economic benefits has become a research hotspot. By analyzing the hydraulic performance of district heating network and the possible flow in each pipe under normal and failure scenarios, we proposed the standby hydraulic design framework. Then, the topology and standby hydraulic design mathematical models of typical single-heat-source single-looped district heating network were established. The variation of hydraulic performance was studied by changing the determination method of design flow, the number, and distribution of users on the mainline. Finally, several design rules which can effectively alleviate the hydraulic imbalance under failure scenarios were proposed. The results show that using the method of weighted summation of the possible flow and its probability in each pipe under various operation scenarios to design pipe diameter has the advantages of high hydraulic performance without greatly increasing investment.