Investigation of three Organic Fluids Effects on Exergy Analysis of a Combined Cycle: Organic Rankine Cycle / Vapor Compression Refrigeration

Abstract

In this study, the energy and exergy analysis of a combined cycle was carried out. This cycle consists of an organic Rankine cycle and a vapor compression refrigeration cycle for producing the cooling effect. Three organic fluids were used as working fluids: the first is isentropic (R123), the second is wet (R134a) and the last is dry (R600). The parametric analysis allowed us to characterize the combined system and to study the effect of some parameters that were used to estimate the thermal and exergy efficiency of the studied system. The comparative study of the combined cycle performance working with organic fluids showed that the isentropic fluid gives the highest value of both thermal end exergy efficiency 51.2% and 25.1%, respectively. The results showed that the operating parameters have a significant impact on the performance of the combined system. On the other hand, the results of the exergy destruction distribution showed also that the exergy is strongly destroyed in the condenser followed by the ORC Evaporator.