Performance analysis of EES-based transcritical carbon dioxide two-stage compression/ejector refrigeration system for shipboard cold chambers

Abstract

Carbon dioxide (CO2) as a natural refrigerant has a broad application prospect in the refrigeration system of shipboard cold chambers. In this work, a novel transcritical CO2 two-stage compression refrigeration system equipped with a two-phase ejector for shipboard cold chambers is proposed. At the same time, simulation of the two-phase ejector and the system was carried out by Engineering Equation Solver (EES). Additionally, The effects of high pressure stage exhaust pressure, intermediate pressure and evaporating temperature on system performance were also investigated. The results showed that the system COP increased with the evap-orating temperature increased from -35°C to -25°C. The system COP decreased with the increase in exhaust pressure, when the evaporating temperature is maintained at -35°C. The optimal intermediate pressure is 4.75 MPa, when the evaporating temperature is fixed at -35°C.