A theoretical model to study of the contribution of potential attractive part on viscosity of real fluid mixtures

In this paper, three real fluid mixtures, such as methane+Ar, methane+Kr and methane+Xe, are considered and the viscosity of the mixtures is theoretically calculated. For this purpose, three potential models are chosen. The potential models have the same repulsive terms but different attractive parts. The main purpose of this paper is to study the contribution of the potential attractive term on the viscosity of the fluid mixtures. To this goal, the Ornstein–Zernike (OZ) integral equation is first solved. Then, the viscosity is calculated by the Vesovic–Wakeham (VW) formalism. The obtained results in this work have been compared with the simulation data and also the experimental results. The findings show that the viscosity at low density for the three potential models is in good agreement with the simulation data. But, at high density, one of the potential models gave better agreement with the experimental results. Also, it is found that for each of the aforementioned mixtures, only one potential model gives a better result in comparison with the experimental data. The lowest deviation with the experimental data corresponds to the mixture of methane+Kr (3.0%) and methane+Xe (3.0%) by using different potential models. It means that the attractive term has an important role in predicting the viscosity of the fluid mixtures.