Lattice Boltzmann modeling of two-phase flows in complex porous media considering surface hydrophobicity

Two-phase flows in porous media with surface hydrophobicity are an important hydro-geomechanical phenomenon in many practical applications, such as irrigation in farming land where soil hydrophobicity impacts efficiency of water use. In this study, a Lattice Boltzmann Method (LBM) is attempted to simulate 2D pore-scale two-phase flows in porous media. Assuming the availability of 2D profiling of the porous media structures (e g. X-ray scanning), 2D digital images coupled with the bounce-back scheme are used as the input to deal with complex geometric boundaries. Based on this method, the detailed information of flow in pore spaces is obtained, and droplet or bubbles spreading and the influences of different wetting properties can be simulated successfully. The numerical method established in this work provides a promising approach to pore-scale flow simulation in porous media with complex geometrical boundaries, which could be applied to predict flow behavior in hydrophobic porous media. (e.g. soils).