Ejector-Compression Cycle as an Appropriate Method for Refrigeration

Importance of energy saving, increasing prices of energy and using non-renewable fossil fuels, make scientists and industrialists to use less power in economic cycles. Among variety of available combined cycles, the one which is a combination of a vapor compression cycle and ejector cycle, is used extensively in food industry and transportation. The energy of this cycle can be provided by solar panels, waste heat in other processes and the heat comes out of car exhaust. In this study, the combined cycle is analyzed in terms of performance, COP, optimization and exergy in the same boundary conditions and for two refrigerant fluids: Propane and R134a. The effect of area ratio (diffuser inlet to the nozzle outlet) on the performance coefficient is investigated. Also, exergy losses of this cycle are compared with the vapor compression cycle. These comparisons are studied for different components of the cycle. Results show that energy losses in this cycle are less than vapor compression cycle, due to the less exergy losses in the parts. The COP values of the ejector-compression cycle are higher than that of the vapor compression cycle. Propane with less global warming potential value than CFCs is more efficient to apply in order to get higher relevant cooling.