Two-phase flow in heterogeneous porous media based on Brinkman and Darcy models

Multiphase flow in porous matrix with embedded free-flowing regions has wide application in industry, environment and biological systems. Due to its permo-porosity characteristics, the free-flow regions, represented by fractures and vugs embedded within the porous matrix, make multiphase flow modeling challenging. This study compares different approaches that can be used to describe two-phase flow through vugular porous media. Brinkman equation is used to describe physical phenomena considering both flow through the porous matrix and through free-flow regions. The predictions obtained with Brinkman model are compared with two different Darcy models: heterogeneous and homogeneous. In the heterogeneous Darcy model, the vugular region is characterized as a porous medium with high porosity and permeability. In the homogeneous Darcy model, the complex two-phase flow through the vugular domain is represented by an equivalent absolute permeability and relative permeability curves. The accuracy of the homogenization procedure is evaluated as a function of vug configuration.