PREDICTION OF PHASE-EQUILIBRIA FOR REFRIGERANT MIXTURES OF DIFLUOROMETHANE (HFC-32), 1,1,1,2-TETRAFLUOROETHANE (HFC-134A), AND PENTAFLUOROETHANE (HFC-125A) USING SAFT-VR
A. Galindo et al., PREDICTION OF PHASE-EQUILIBRIA FOR REFRIGERANT MIXTURES OF DIFLUOROMETHANE (HFC-32), 1,1,1,2-TETRAFLUOROETHANE (HFC-134A), AND PENTAFLUOROETHANE (HFC-125A) USING SAFT-VR, JOURNAL OF PHYSICAL CHEMISTRY B, 102(39), 1998, pp. 7632-7639
The statistical associating fluid theory for chain molecules with attr
active potentials of variable range (SAFT-VR) is used to model the pha
se equilibria for three binary mixtures formed by difluoromethane (HFC
-32), 1,1,1,2-tetrafluoroethane (HFC-134a), and pentafluoroethane (HFC
-125a). Molecules are represented as chains of spherical segments with
short-ranged attractive-sites. The intermolecular van der Waals force
s are modeled with variable-range square-wells. The optimized values o
f the parameters of the model rue obtained by fitting to experimental
data for the vapor pressures and saturated liquid densities of each of
the pure components. These parameters are the number and diameters of
the spherical segments and the strengths and ranges of the potentials
describing the site-site and segment-segment interactions. Using the
values of the pure-component parameters and standard combining rules,
the phase equilibrium of the mixtures is described very accurately. SA
FT-VR improves the predictive power of mean-field versions of SAFT.