Performance improvement on diffusion absorption refrigeration system design and manufacture by experimental and theoretical analysis

In this study, diffusion absorption refrigeration (DAR) system was investigated experimentally and theoretically. Ammonia, water and helium were used in DAR as the refrigerant, absorber, and diffuser respectively. The system which was designed and made was heated by electricity, LPG as an alternative fuel, and solar energy, as a renewable energy source. Two different systems were designed to improve the performance of the electric heater: i) a system without condensate subcooling was made by modifying the subcooling system (DAR2), ii) an ejector is inserted into the line before the absorber of the subcooled system (DAR3). With electricity as the heat source, DAR1 system reached the lowest temperature (3oC) inside the refrigerator, and DAR2 system showed the best COP (27%) due to its high flow rate. Besides the system performance of DAR1 was improved by 26% by using ejector (DAR3). Running the system on renewable energy, it was experimentally shown that our rich resources of solar energy can be used in cooling system.Keywords: Ammonia, water, helium, absorption refrigeration, ejector