Lattice Boltzmann method for modeling liquid-vapor interface configurations in porous media

The lattice Boltzmann method (LBM) has emerged as a powerful tool for simulating the behavior of multiphase fluid systems in complex pore networks. Specifically, the single component multiphase LBM can simulate the interfacial phenomena of surface tension and adsorption and thus be used for modeling fluids such as water and its vapor in porous media. This paper provides an introduction to LBM applications to interface configurations in partially saturated porous media. Key elements of this LBM application are fluid-fluid and fluid-solid interactions that successfully mimic the Young-Laplace equation and liquid film adsorption. LBM simulations of liquid behavior in simple pore geometry considering capillarity and adsorption are in good agreement with analytical solutions and serve as critical first steps toward validating this approach. We demonstrate the usefulness of LBM in constructing virtual liquid retention measurements based on porous media imagery. Results of this study provide a basis for application of LBM to understanding liquid configurations in more complex geometries and clear a path for applications involving interface migration, flow, and transport in partially saturated porous media.