Abstract |
The report gives results of miscibility, solubility, viscosity, and density measurements for refrigerant R-236fa and two potential lubricants. (The data are needed to determine the suitability of refrigerant/lubricant combinations for use in refrigeration systems.) The tested oils were pentaerythritol ester mixed-acid (ISO68), hereafter SW-68 manufactured by Castrol, and polyol ester mixed-acid (ISO46), hereafter Arctic-46 manufactured by Mobil. Miscibility was measured in a series of miniature test cells submerged in a constant temperature bath, precisely controlled over a temperature range of -50 to 90 C. Solubility, viscosity, and density data were also obtained for R-236fa mixed with the two oils for a refrigerant concentration of 0 to 40 wt % refrigerant over a temperature range of 30 to 100 C. This research shows that: (1) solubility, viscosity, and density are functions of temperature and concentration, (2) solubility increases with increasing temperature and refrigerant concentration (i.e., mass fraction of refrigerant). (3) viscosity decreases with increasing temperature and refrigerant concentration, and (4) density decreases with increasing temperature but increases with increasing refrigerant concentration. R-114 and naphthenic mineral oil were also tested. |