Viscosity and Density of an ISO VG 32 Polyol Ester Lubricant Saturated with Compressed Hydrofluorocarbon Gases: R-134a, R-32, and R-125

Abstract

The dynamic viscosity and density measurements for mixtures of synthetic polyol ester (POE) lubricating oil (ISO VG 32) saturated with compressed 1,1,1,2-tetrafluoroethane (R-134a), pentafluoroethane (R-125), and difluoromethane (R-32) were conducted over a wide temperature range (248.15 K, 273.15 K, 323.15 K, and 348.15 K) and pressures up to 1.0 MPa. The viscosity and density data ranged from 2845 to 6 mPa•s and 1019 to 948 kg•m −3 , respectively. Previously reported vapor−liquid equilibrium and modeling data were used to predict the liquid composition for both viscosity and density as a function of temperature and pressure. Redlich−Kister expansions were used to correlate the measured viscosity and density for each HFC/lubricating oil system. Experimental and modeling data were used to calculate the kinematic viscosities and generate Daniel plots.