Abstract
The paper presents new measurements on the viscosity for the mixtures of R134a and polyolester oil at low oil-concentrations. The measurements were conducted with a newly developed oscillating cup viscometer making use of polarizer at oil-concentrations between 0 and 16 mass% and temperatures from 278.15 K to 288.15 K. The uncertainty in viscosity was estimated to be less than ±4.3%. It was found that even a small amount of the oil into R134a had a significant effect on the viscosity. It increased exponentially with oil-concentration. Mixing the oil into R134a up to an oil-concentration of 16 mass% tripled the viscosity. A correlation equation as a function of temperature and oil mass fraction was formulated to interpolate the experimental viscosity data.
