Semi‐Analytical Modeling of Rate‐Dependent Relative Permeability in Heterogeneous Formations

Relative permeability ( k r ) is an important property characterizing multi‐phase flow in porous media, in particular considering applications of oil and gas production or CO 2 storage in subsurface formations. Coreflooding experiments are the most common method of determining k r , usually conducted at a given total injection rate. However, k r is known to be a rate dependent effective property due to capillary heterogeneity effects and therefore full characterization requires conducting experiments at different flow rates, a complex and time consuming process. This work presents a new approach for calculating rate dependent effective k r curves based on a 1D semi‐analytical solution for steady state flow. The method entails calibrating a 1D permeability structure to represent the 3D flow of coreflooding experiments. Then, the calibrated 1D model is used to estimate k r curves at varying rates. We apply the method to three cases, two synthetic and one based on experimental data. Results show applicability for a wide range of flow rates.