Impact of pore-scale corner and film flows on macroscopic transport in porous media

Capillary pressure-saturation and relative permeability curves are crucial for predicting multiphase fluid flow behavior in porous media, directly influencing the efficiency and reliability of subsurface engineering applications. At low saturations, the wetting-phase flow transitions from bulk displacement to being governed by corner and film flows along pore surfaces. Recent experiments and pore-scale simulations have shown that these microscale flow mechanisms preserve fluid connectivity and continue to influence macroscopic transport behavior, even after bulk flow pathways are no longer active. This work synthesizes current experimental and computational findings, highlighting how the formation and persistence of microscale flow networks made of corner and film flows influence capillary pressure and relative permeability curves, especially by enhancing wetting-phase connectivity at low wetting-phase saturations. Finally, key directions for future research are proposed to further enhance the understanding of how microscale film and corner flows influence macroscopic multiphase flow characteristics. Document Type: Perspective Cited as: Lan, T., Hu, R., Zhao, B. Impact of pore-scale corner and film flows on macroscopic transport in porous media. Capillarity, 2025, 16(1): 1-4. https://doi.org/10.46690/capi.2025.07.01