LAUSR

Abstract Trifluoroethene R1123 is expected to be a low GWP refrigerant; however, it needs to be mixed with other stable refrigerants to avoid a disproportional reaction. This paper delivers one of the essential thermophysical properties surface tension for a low-GWP refrigerant mixture R1123/R32/1234yf measured by the differential capillary rise method in the temperature range from 225 to 345 K. The propagated uncertainty in surface tension with a 95% confidence level was typically 0.15 mNm−1. From the measured surface tension and calculated saturation densities, the parachor of R32 and R1123 were determined to be 91.6 and 123.3, respectively. The parachor of R1234yf was slightly dependent on a temperature, T, as 181.44−0.0319T. The variation in the surface tension of binary pairs against the composition was predicted by the correlation proposed by Di Nicola et al. (2018) and the parachor method with sufficient accuracy. Furthermore, the surface tension of ternary mixture R1123/R32/1234yf at compositions of 60/22/18 mass% and 22/70/08 mass% was also predicted by the parachor method with sufficient accuracy. Nevertheless, a slight deviation was confirmed at temperatures below 260 K. The prediction would be improved with subsequent studies in phase equilibrium. (191 words)