Parametric study of absorption refrigeration with vapor compression refrigeration cycle using wet, isentropic and azeotropic working fluids: Conventional and advanced exergy approach

Abstract

Advanced exergy analysis was carried out for absorption-compression refrigeration-cycles with a working fluid selection and parametric analysis. The exergy-destruction was split into endogenous-exogenous and avoidable-unavoidable-parts to reveal the interdependency within the components and determine the improvement potential. The results show that the largest exergy-destruction occurs in the generator, accounting for 53.8% of the total destruction. The largest irreversibility occurs for R507a/NH3–H2O while the lowest destruction occurs for R152a/NH3–H2O with an approximate reduction of 0.62 kW. The largest irreversibility occurs in the azeotropic-fluids while the lowest occurs in wet fluids. More than one-half of overall exergy-destruction rates of the systems falls into the part of the avoidable-destruction with 52.5% of overall irreversibility. The major part of the avoidable-destruction occurs in the generator with 11.47 kW and it accounts for 57.8% of the total avoidable part, meaning that it has the highest improvement potential. The parametric analysis of the advanced exergy shows that the avoidable-part of the exergy-destruction can be minimized to a considerable extent employing a temperature of the condenser below 40 °C and generator temperature larger from 100 °C.