Keywords: R-404A, exergy analysis, inter-stage pressure, two-stage refrigerating cycle, vapour compression, second law analysis, refrigeration plants, direct liquid injection, subcoolers, energy analysis, equivalence criterion
Second-law analysis of two-stage vapour compression refrigeration plants
This paper describes a Second Law Analysis based on experimental data of a two-stage vapour compression facility driven by a compound compressor for medium and low-capacity refrigeration applications, which operates with the most usual inter-stage configurations (direct liquid injection and subcooler). The experimental analysis is performed for an evaporating temperature range between ?36°C and ?20°C and for a condensing temperature range between 30°C and 47°C using the refrigerant R-404A. The final results are compared with energy analysis from previous works. Additionally, a new criterion of equivalence between the simple vapour compression cycle and the two-stage compression cycle is given.