This study presents a pore-scale simulation of two-phase flow in a realistic rock model of Tuscaloosa sandstone under strong-, intermediate- and weak-wet conditions. An optimized colour–gradient lattice Boltzmann (LB) model is adopted to simulate two-phase flow in a rock sample, and a D3Q19 multiple–relaxation–time (MRT) LB scheme has been applied
These visualizations display the displacement pattern of the invaded fluid, which has a ramified pattern under the strong drainage conditions (large θ). However, the coroner flow mechanism prevails under imbibition condition (small θ) in which filling of smaller pore throats is favored over large pores. As the wettability of a porous medium changes to an intermediate-wet condition, complication in fluid physics arises, as a mixed population of concave and convex interfaces appear in the displacement front.
The present study remarkably contributes to assessment of sweep efficiency and storage capacity of CO2 storage projects and provides information on the behavior of these multiphase systems in contact with rock formations having various wetting properties.