Abstract :
A model Ibr estimating second and third virial coefficients, which has been used
successfully to rcpresent the behavior of pure gases and binary mixtures, was
applied to a ternary mixture. An estimate for the ternary third virial coefficient,
Ct_, 3, was added to the model. Three experimentally determined binary interaction
parameters were also used. The model has been applied to the ternary
mixture CH_,F_,+CF,CHF_,+CF3CH,F (R32+RI25+RI34a). The rest.Its
are useful Ibr calculating gas-phase densities, thermodynamic properties, and
fugacities Ibr phase equilibrium calculations. The use of such models leads
to a considerable economy of effort in the case of multicomponent mixtures.
Examples of the thcrmodynamic properties are given for the equimolar ternary
mixture in the range from the dew-point temperature to 400 K at pressures of
0.5, I, and 2 MPa. Calculated densitics and speeds of sound are compared with
new experimental values Ibr at near-equimolar composition.
