Importance of molecular interaction description on the hydrodynamics of gas mixtures

Abstract

The aim of this study is to analyze the hydrodynamics of gas mixtures invoking a recently proposed multifluid model. The model consists of a separate equation set for one component species of the system and an equation set for average quantities of the mixture. Thereby, it provides details of the flow fields for each of the constituents separately. The new model also computes transport coefficients from some kinetic relations without the requirement of being input externally. Moreover, it automatically describes diffusion processes excluding the use of any coefficients for ordinary, pressure and thermal diffusion, which are generally required during Navier–Stokes computation of gas mixture flows.In the present paper, the model that was applied with hard-sphere molecules is extended to include more realistic molecular interaction descriptions (i.e. Maxwell repulsive potential and Lennard-Jones 12–6 potential). Moreover, the contribution of external forces is incorporated in the multifluid balance equations. Afterwards, the resulting equations are solved for some gas mixture problems in the context of a converging-diverging nozzle, and the importance of the molecular interaction description on the hydrodynamics of the mixtures is analyzed.