Assessment of the Effect of Mixing Rules on Transport Properties of Gas Mixtures

Abstract

Abstract The purpose of this paper is to examine the effect of six different mixing rules on the calculated transport properties including viscosities and thermal conductivities of some binary and ternary gas mixtures. These properties are calculated using pair potential energies of the systems obtained from the inversion procedure. The Chapman–Enskog theory and Schreiber’s method are employed to calculate viscosity and thermal conductivity of different mixtures, respectively. Different mixing rules do not behave the same in predicting the two aforementioned properties. The Fit (MADAR-2) mixing rule gives rise to more acceptable viscosity values, while the Halgren-HHG rule stands over other mixing rules in predicting thermal conductivity. It is found that, when the mixture components are similar in size, different mixing rules often do not change the errors in calculated properties more than ±1%. However, as the size similarity decreases, the effect of applied mixing rules becomes more important. In this case, different mixing rules are able to change the errors in calculations at most ±3.5%. The collision diameters (σ) of our studied mixture components, vary from 2.641 Å for He, to 5.26 Å for R125. The energy scaling parameters (ε) of mixture components range from 10.956 K for He to 475.76 K for C4H10.