Dynamics of the flow of a dense fluid in narrow pores

A new approach was employed for the theoretical study of a dense fluid flow (gas and liquid) in narrow pores. Calculations were made on the basis of the Navier-Stokes equations. The transfer coefficients and the equations of state were derived within the framework of the simplest molecular model, namely, the lattice gas model. This model takes into account the volume of molecules and their interaction with one another. The transfer coefficients and the equations of state prove to be dependent on the local values of the fluid density and temperature. A study was performed into the dynamic modes of flow of a monoatomic gas (argon) in slitlike pores of various widths at a given pressure drop across the pore ends. It was shown that, at low densities, there is a high anisotropy of the flow owing to the attraction of argon atoms to the pore walls, which gives rise to a strong dependence of the local viscosity on the distance from the pore wall and to the film flow. An investigation was carried out into the dynamics of the interaction between the gas and liquid zones, which is accompanied by the breakdown of the interface.