Vaopr-Liquid Critical Point for the Ternary Difluoromethane + Pentafluoroethane + 1,1,1,2-Tetrafluoroethane (R-32/125/134a) Mixture

Published

October 16, 2008

Author(s)

Yukihiru Higashi

Abstract

The vapor-liquid critical point for the ternary refrigerant mixture of difluoromethane (R-32) + pentafluoroethane (R-125) +1,1,1,2-tetrafluoroethane (R-134a) was determined from the vapor-liquid coexistence curve data near the mixture critical point. The compositions of the measurement are 23 mass percent R-32+25 mass percent R-125+52 mass percent R-134a(R-407C), 25 mass percent R-32+15 mass percent R-125+60 mass percent R-134a(R-407E), and 20 mass percent R-32+40 mass percent R-125+40 mass percent R-134a(R-407A). The critical temperature of this mixture was determined by the observation of the meniscus disappearance. The critical density of this mixture was determined on the basis of the meniscus disappearance level and the intensity of the critical opalescence. The uncertainties of the temperature, density, and composition measurements were estimated within +or-} 10mK, +or-} 5 kg m^-3, and +or-}0.05 %, respectively. In addition, the predictive methods of the critical parameters for the R-32/125/134a mixture are discussed.

Citation

International Journal of Thermophysics

Pub Type

Journals

Keywords

critical point of mixture, R-32/125/134a refrigerant mixture, R-407A, R-407C, R-407E, saturated densities, vapor-liquid coexistence curve

Citation

Higashi, Y. (2008), Vaopr-Liquid Critical Point for the Ternary Difluoromethane + Pentafluoroethane + 1,1,1,2-Tetrafluoroethane (R-32/125/134a) Mixture, International Journal of Thermophysics (Accessed April 26, 2024)