Simulation And Experiment Study On The Quasi Two-Stage Compression Heat Pump System Coupled With Ejector

The quasi two-stage compression heat pump system with economizer can effectively improve the deficiencies of conventional air-source heat pump when running in low ambient temperature. On the base of the quasi two-stage compression heat pump system with economizer, considering that it can make use of the pressure energy of liquid with high pressure and minish energy losing of the system, ejector is adopted to replace the throttle in the assistant loop, and design the quasi two-stage compression heat pump system coupled with ejector. The method is adopted that combining theory analysis and experiment to study this system detailedly.In the paper, interrelated background and working principle of the quasi two-stage compression heat pump system coupled with ejector are introduced in detail firstly. Working process of ejector and scroll compressor with supplementary inlet are analysed mainly and the mathematic model of the system is set up. On this base, the main performances of the system are calculated and compared with those of the heat pump system with flash-tank coupied with sroll compressor to analyse their difference. The conclusion is drawn that in the quasi two-stage compression heat pump system coupled with ejector, discharge temperature of the compressor is decreased effectively, electric power is reduced , and heating performance is increased compared with those of the flash-tank throttle system in the same conditions. It shows that the quasi two-stage compression heat pump system coupled with ejector improves performances of air-source heat pump in theory.Ejector is a key part of the system, its structure size must be accurate. In the given work condition, its structure is designed, experiment project is designed and performances of prototype are tested to prove theory analysis. At the same time, experiment data of the prototype are compared with those of the conventional system and the flash-tank throttle system to test the correctness of the theory.At last, exergy of the quasi two-stage compression heat pump system coupled with ejector is analysed, such as exergy loss, exergy efficiency and exergy loss distributing, and compared with those of the flash-tank throttle system. It shows that the quasi two-stage compression heat pump system coupled with ejector can make use of energy more effectively, which proves that the point of the task is correct.This study will quicken the development of heat pump industries, expand the...