Simulation Study of a Heat Pump Dual Temperature Display Cabinet Using Two Natural Refrigerants

The dual-temperature display cabinet stores hot and cold products in the same unit and requires a heat source in addition to the refrigeration system. The heat is provided by an electric heater in a baseline system and can be replaced by leveraging condensing-heat. Two natural fluids were numerically investigated in this study, R290, and R744. Experimental data from a baseline dual- temperature display cabinet validated the numerical model in this study. Among the geometric and operating parameters of the two heat exchangers, it was found that the most important parameter is the air volumetric flow rate of the condenser. In the medium and high temperature environment, the R290 has a better energy-saving effect, while the R744 is more suitable for low temperature conditions. When the ambient temperature is 25°C, the power consumption of the heat pump system using the R290 and R744 has 49% and 43% energy saving benefits over the baseline, respectively.