To investigate the effect of supply air temperature on the comprehensive performance of a vehicle transcritical CO2 refrigeration system

a simulation model of a single-stage transcritical CO2 refrigeration system is established using the GT-Suite simulation software. Based on three designed operating conditions

system performances under different supply air temperatures are compared

the upper limit of the air volumetric flow rate is specified

and the concept of the effective coefficient of performance (COPeff) is proposed and analyzed. Under the same conditions

increasing the supply air temperature can improve the system coefficient of performance (COP)

COPeff

and the effective COP with fan power consumption. Under low cooling load conditions

the optimal value of COPb is 3.819

implying that the air supply temperature is optimal. However

when the cooling load increases to a certain level

the optimal air supply temperature is no longer valid. The research presented herein guides the selection of the supply air temperature for vehicle transcritical CO2 refrigeration systems.