Construction of Relative Permeability Curves by Numerical Simulation of Two-Phase Flow in 3D CT-Models

The paper describes an algorithm for constructing relative phase permeability curves based on a numerical simulation of primary drainage and subsequent water re-saturation. These processes are simulated as two-phase fluid flows in three-dimensional models generated from CT-images. We use the Navier-Stokes equations to simulate the flow and the Cahn-Hilliard equation to model phase transport. In the applied phase field method, phases are specified by a concentration function. This function is smooth so that the interphase boundary is replaced by a fairly thin layer in which the values of the concentration function continuously change. This representation makes it possible to robustly calculate surface tension forces and take into account the contact angle when using the finite difference method for numerical modeling of fluid flows and phase transport.