Exergetic analysis of a refrigeration system

This paper presents the exergy analysis of an experimental refrigeration system that operates with the refrigerant R134a. The research is based on analyzing the influence of six operational and controllable parameters of the experimental setup such as the compressor frequency of operation, the degree of static superheat, and the temperature of the secondary fluids (at the inlet of the evaporator and the condenser) on the exergy destruction. Thus, the results show that most exergy destruction is located in the condenser, followed by the compressor, the expansion valve and the evaporator. Furthermore, the highest exergetic effciency is obtained by a decrease in the temperature of the secondary fluid inside the evaporator, and by an operation of the compressor at low speed. The effciency of the compressor is also included in the analysis, which is a parameter that determines the exergy destruction of the largest component. Finally, a function of the exergetic effciency is established in order to find those magnitudes of operational parameters that contribute to improving this effciency.