| We present a new dynamic pore network model that is capable of up-scaling two-phase flow processes from pore to core. This dynamic model provides a platform to study various flow processes in porous media at the core scale using the pore-scale physics. The most critical features of this platform can be listed as (1) the inclusion of viscous, capillary, and gravity pressure drops in pore-scale displacement thresholds, (2) wetting-phase corner flow in capillary elements with angular cross-sections, (3) adjustments of corner interfaces between wetting and non-wetting phases based on changes in local capillary pressure, (4) simultaneous injection of wetting and non-wetting phases from the inlet of the medium at constant flow rates that makes the study of steady-state processes possible, (5) heavy parallelization using a three-dimensional domain decomposition scheme that has enabled us to study two-phase flow at the core scale, and (6) constant pressure boundary condition at the outlet. For the validation of the dynamic model, three two-phase miniature core-flooding experiments were performed in Berea and Bentheimer sandstone core samples. The experiments were performed in a state-of-the-art core-flooding system integrated with a high-resolution X-ray micro-CT scanner. In-situ contact angles that are measured from high-resolution micro-CT images of the pore space during the experiments are used to design contact angle distributions in the digital pore space. Simulations are performed in the pore networks constructed from high-resolution micro-CT images of the core samples used in the experiments. In order to replicate the fluid systems of the experiments, fluid properties are measured in laboratory at the experimental conditions and fed to the dynamic model as inputs. The dynamic model is rigorously validated, by comparing the predicted local saturation profiles, fractional flow curves, relative permeabilities, and residual oil saturations with their experimental counterparts. The validated dynamic model is then used to study low-IFT and high viscosity two-phase flow processes and investigate the effect of high capillary number on relative permeabilities and residual oil saturation. |
