Evaluation on the cooling capacity of a cascade cold storage refrigeration system using refrigerant pair R513A/R744

This paper presented in a cascade cold storage refrigeration system using a R513A/R744 pair by the experimental method. The R744 refrigerant was used for the low temperature cycle (LTC) and R513A was used for the high temperature cycle (HTC). The experimental data on the thermodynamic properties were collected at an ambient temperature of 32oC. Following this study, the thermal parameters of those refrigerants in CRS were indicated detailly, the temperature of cold room was gone from 32oC down to -20oC in 35 minutes. The R744 refrigerant in LTC has a condensing temperature of 5.9oC and an evaporating temperature of -25oC, experimenting with the cooling capacity reached 1.35 kW and the overall COP reached 2.0. Moreover, those theory results are suitable with experimental data, the differential error is less than 10%.