Performance Analysis of Low-GWP Refrigerant Mixture Used in Automotive Heat-Pump Air Conditioner

The basic thermophysical properties and cycle performances of refrigerant mixtures are compared and analyzed in automotive heat pumps. The following mixtures are analyzed:R134a, R1234yf, R290, R410A, and eight mixtures containing flame retardant R1216, including five binary mixtures comprising R1234ze(E), R152a, R1234yf, R290, and R127 with R1216 and three ternary mixtures, R1234yf/R161/R1216, R134a/R161/R1216, and R1123/R32/R1216. The results show that all the mixtures are environmentally friendly and stable in operation, with Global Warming Potential (GWP) values lower than 150 and temperature glide lower than 3 ℃. R152a/R1216 (60/40) has similar thermophysical properties and cycle performance when compared to R134a and exhibits an approximately 11% increase in the heating coefficient of performance (COP). R290/R1216 (60/40), R1270/R1216 (60/40), R1234yf/R161/R1216 (40/40/20), and R134a/R161/R1216 (10/50/40) exhibit higher volumetric cooling/heating capacities, ranging from 113% to 180% that of R134a. R1123/R32/R1216 (60/20/20) has a lower cooling COP than R134a and R410A by 84% and 93%, respectively. However, it has the highest volumetric performance, outperforming R134a and R410A by approximately 104% and 109%, respectively. These refrigerant mixtures may be applied to small mobile cooling systems such as electric-vehicle heat pumps; however, further experimental validation is necessary for their application and promotion.