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Vapor-Liquid Equilibrium for the Binary Difluoromethane (R-32)+ Propane (R-290) Mixture
Published
Author(s)
Yukihiru Higashi
Abstract
The vapor-liquid equilibrium of the mixture composed of difluoromethane (R-32) and propane (R-290) was studied in the temperature range between 273.15 K and 313.15 K. The experimental uncertainty of temperature, pressure, and compostion measurements were estimated to be within +or-} 10 mK, +or-} 0.4 %, and +or-} 0.4 mol %, respectively. The comparison between the present data and avaliable experimental data was made using the Helmholtz free energy model equation of state (HMX-EOS) adopted in the thermophysical properties program package, REFPROP 6.0, as a baseline. In addition, the existence of an azeotrope and the determination of new adjustable parameters for HMX-EOS for the R-32 + R-290 mixture are also discussed.
Citation
International Journal of Thermophysics
Pub Type
Journals
Keywords
alternative refrigerants, azeotropic mixture, Helmholtz free energy model equation, R-32+R-290 mixture, REFPROP 6.0, vapor-liquid equilibria
Citation
Higashi, Y.
(2008),
Vapor-Liquid Equilibrium for the Binary Difluoromethane (R-32)+ Propane (R-290) Mixture, International Journal of Thermophysics
(Accessed October 10, 2025)