VISCOSITY OF R134a/OIL MIXTURES AT AMBIENT TEMPERATURES AND LOW OIL-CONCENTRATIONS

摘要

This paper describes viscosity measurements for R134a/PAG and R134a/POE saturated liquid mixtures at 283 K for low oil-concentrations 0 to 16 mass%. An oscillating-cup viscometer making use of polarizers was used for the measurements. The decrement was obtained by detecting the change of light intensity passing through two polarizers and analizing the damping angular displacement. The overall uncertainty in viscosity was estimated to be less than ±4.3% for both R134a/PAG and R134a/POE mixtures. The measurements show that the R134a/PAG and R134a/POE mixtures at an oil-concentration of 16 mass% are approximately three to four times more viscous than R134a. The comparison shows that the effect of PAG on viscosity is slightly greater than that of POE.