Abstract
Gas-liquid two-phase flows in porous structures are simulated by the lattice Boltzmann method for two-phase fluids with large density differences, in which the wetting boundary condition on solid walls is incorporated. The behavior of the liquid phase penetrating the hydrophobic and hydrophilic microchannels is investigated. The curvature radius and the average height of the liquid phase in equilibrium are calculated, and found to be in good agreement with the theoretical predictions. In addition, the behavior of the liquid phase in porous structures with various porosities is simulated for hydrophilic and hydrophobic cases. From these results, it is found that the liquid phase in the porous structure is transported from the hydrophobic to hydrophilic regions, and that the liquid tends to penetrate in locally narrow spaces owing to the effect of large pressure gradient.
