Numerical Study of Water and Polymer Flooding in an Oil-Wet Heterogeneous Porous Medium

In recent decades, as oil reservoirs near their half-life, enhanced oil recovery (EOR) techniques, including water and polymer flooding, have become increasingly important and widespread. Hence, a computational fluid dynamics (CFD) model was employed in this research to simulate a two-phase flow in an oil-wet heterogeneous porous medium. The Navier-Stokes and phase-field equations were coupled by COMSOL multiphysics software to describe oil-water flow in pore structure and trace the interface of phases. The system of equations was discretized by the finite element method (FEM), and then the weak form of equations was solved. In the next section of this study, a sensitivity analysis was performed, and the influence of effective parameters such as wettability, viscosity ratio, and heterogeneity was investigated. Finally, polymer flooding is proposed as a remedy for increasing water sweep efficiency and declining residual oil. It was observed that polymer flooding increased oil recovery by ۷۹%.