Modeling of Flow and Transport in Multiscale Digital Rocks Aided by Grid Coarsening of Microporosity

Abstract

Many subsurface and industrial porous media such as carbonate rocks, filters, and catalysts possess multiscale porous structures that play an important role in regulating fluid flow and transport therein. A pore-network-continuum hybrid flow model is promising for numerical studies of a multiscale digital rock. It is, however, still prohibitive to the REV-size modeling because tens of millions of microporosity voxels may exist. In this talk, I will introduce a novel and robust algorithm for coarsening microporosity voxels of a multiscale digital rock. Then, we combine coarsened microporosity grids with the pore network of resolved macropores to form efficient computational meshes. Furthermore, a pore-network-continuum simulator is developed to simulate flow and transport in both synthesized multiscale digital rocks and realistic carbonate and tight rocks. I will show that the coarsening algorithm can reduce computational grids by about 90%, which substantially reduces computational costs. Meanwhile, coarsening microporosity has a minor impact on the predictions of absolute permeability, gas production curves, and breakthrough curves of solute transport. Finally, I will present the application of the hybrid model in the modeling of capillary pressure and relative permeability curves of tight sandstones. The developed pore-network-continuum hybrid model aided by grid coarsening of microporosity serves as a useful numerical tool to study flow and transport in multiscale porous media.

Short Bio

Prof. Qin Chaozhong is from the Department of Carbon Storage Science and Engineering, Faculty of Resources and Safety Engineering, Chongqing University. He obtained his doctoral degree from the Department of Earth Sciences, Utrecht University, The Netherlands in 2013, under the supervision of Prof. Majid Hassanizadeh. He served as the Managing director of the Darcy Research Center at Eindhoven University of Technology from 2016 to 2019. He joined Chongqing University at the end of 2019. Currently, his research interests mainly focus on multiscale flow and transport in porous media and digital rock analysis. He has published over 50 articles in peer-reviewed top journals including Geophysical Research Letters, Water Resources Research, Advances in Water Resources, and Journal of Petroleum Science and Engineering.