New molecular approach to theoretical investigations of fluid flows in narrow pores

Abstract

Abstract A new approach has been offered to calculate dense fluid flows in narrow pores. The local properties of fluids are calculated on the basis of the simple molecular model—the lattice-gas model. Molecular interactions are taken into account in quasi-chemical approximation, preserving effects of correlation between nearest neighbours. The model covers a wide range of changes of fluid density (from gaseous up to a liquid state) and temperature including the critical range that permits to consider dynamics of fluid flows at the presence of the capillary condensation, A system of equations has quasi-hydrodynamic type and the approach can be considered as micro-hydrodynamic one. Numerical analysis of the Navier–Stokes type equations predicted by the model was performed by a ‘relaxation’ method with second order accuracy in the temporal and spatial domains. The approach was used for the analysis of dynamic modes of flows for argon gas in carbon slit-like pores. Possibilities of the new approach are demonstrated for four types of steady-state and non-steady-state regimes of molecular flows in narrow slit-like pores.