A proposed combination model for predicting surface tension and surface properties of binary refrigerant mixtures

• Simultaneous prediction of the surface tension, composition and mole density of the binary refrigerant mixtures.
• Performing in a predictive manner with no adjustable parameters.
• Applying fugacity to perform phase equilibrium calculations.
• Performing well compared with the well recognized gradient theory.

A combination model is proposed to describe the surface tension and surface properties of binary refrigerant mixtures combining the Laaksonen and Kulmala equation with the phase equilibrium between the bulk liquid and surface phases to predict the surface tension, surface composition and surface mole density of the binary refrigerant mixtures. Also, the present model is combined with the volume-translated Peng–Robinson (VTPR) equation of state to describe the fugacity coefficients of the components and molar volumes of the bulk and surface phases. This proposed combination model is subsequently applied for 13 binary refrigerant mixtures and compared with the gradient theory. The results of this model show that the surface tensions predicted by this model agree well with experimental data for these mixtures (overall AAD ∼4.35). Compared with the gradient theory (overall AAD ∼5.67 and 3.94 for density and temperature dependant influence parameter), the proposed combination model performs well.