Performance Study On An Ejector Used In CO₂-Heat Pump Water Heater

Through out the world, CFCs has been phased out and HCFCs will be phased out as working fluids in refrigeration, air conditioning, and heat pump applications. Carbon dioxide receives much concern as a new working fluid. Heat pump is recognized as an effective energy-saving technology, scholars at domestic and foreign have conducted an in-depth study on CO₂-heat pump water heater. An ejector is a device with features of simple structure and low cost. Instead of a throttling valve, an ejector can recover the throttling losses to obtain higher heating-COP in CO₂-heat pump water heater. The main researches of this thesis are as follows:1. Analyze the thermodynamic process on the ejector. A constant pressure mixing model for ejector is established by the aerodynamics method.2. Make a software for performance calculation and discuss the effect on entrainment ratio by operating parameters and structure of the ejector.3. Describe a thermal calculation method on CO₂-heat pump water heater with an ejector.4. Describe the determination of specific components and build the test rig of CO₂-heat pump water with an ejector.5. Test, analyze and summarize the performance of the ejector.