Conventional and advanced exergy analysis of a dual-evaporator transcritical CO₂ refrigeration system enhanced with ejectors.

Based on two conventional dual-evaporator systems, this study introduces ejectors and combines traditional exergy analysis with advanced exergy analysis to conduct an in-depth comparison and optimization of four systems. The main objective of the study is to refine the exergy loss distribution, evaluate the improvement potential of each component, and provide a basis for system optimization. The results show that the introduction of ejectors significantly reduces the system’s exergy losses and improves exergy efficiency, with the dualevaporator transcritical CO₂ refrigeration cycle with two compressors (ERCC) system performing the best. Under given conditions, the exergy losses of ejector-enhanced dual-evaporator transcritical CO₂ refrigeration cycle with PRV (ERCV) and ERCC systems are reduced to 60 % of those in conventional systems, with exergy efficiencies increased to 53.69 % and 45.28 %, respectively. Additionally, gas cooler pressure has a significant impact on system performance, and the pressure maintaining under 9 MPa can significantly improve exergy efficiency. Advanced exergy analysis reveals that the endogenous exergy destruction is mainly caused by irreversibility, and compressor2 and compressor in ERCC and ERCV should be optimized first, which can improve the system efficiency by 75.36 % and 65.16 %, respectively.