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.