Binary two-phase flow with phase change in porous media

Flow of multicomponent mixtures with interphase mass transfer through porous media has been analyzed by combining thermodynamics of real fluids, the use of immiscible Boltzmann code and reconstructed porous media. A general algorithm is detailed and applied for comparison with Poiseuille flow where a semi-analytical solution can be found. A series of structures and phenomena are then analysed; attention is mostly focused on liquid to gas transition (or vaporization) and retrograde condensation, phase distribution and macroscopic quantities such as composition, liquid saturation and pressure evolution are systematically plotted. The role of the location of nucleation sites is shortly investigated with a periodically constricted tube. The total mass flow rate influenced the phase distribution and circulation in a two-dimensional network. Finally, relative permeabilities of a reconstructed medium are discussed; an interesting feature is that they follow hysteresis cycles for retrograde condensation. (C) 2001 Elsevier Science Ltd. All rights reserved,