Experimental determination of the optimum intermediate and gas-cooler pressures of a commercial transcritical CO2 refrigeration plant with parallel compression

Abstract CO2 systems used in refrigeration are becoming more complex with the aim of improving their energy performance. Parallel compression is one implemented solutions to enhance performance plants. However, an optimization process required operate this system at high and its operation subjected physical limitations real This work presents experimental a transcritical plant working parallel compression. The tested different discharge pressures secondary compressor speeds order optimize COP determine optimal conditions for three gas-cooler exit temperatures 27.5 °C, 32.5 °C 37.5 °C evaporation levels: −15.0 °C, −10.0 °C −5.0 °C. that can be achieved have been determined, obtaining from 1.71 2.63 −5.0 °C, 1.50 2.22 1.25 1.84 −15.0 °C. Cooling capacity ranges 8.94 kW 11.34 7.71 kW 9.47 kW 6.22 kW 7.76 kW trends observed theoretical results corroborated optimum intermediate determined discussed.