Interplay of viscosity and wettability controls fluid displacement in porous media
Saideep Pavuluri, Ran Holtzman, Luqman Kazeem, Malyah Mohammed, Thomas Seers, Harris Sajjad Rabbani
Abstract
The interplay between viscosity ratio and contact angle for viscous-dominated flows in a two-dimensional porous medium is studied with Direct Numerical Simulations. Viscous fingering, intermediate flow, and compact displacement regimes were examined for various viscosity ratios at the sample scale. Even at the pore-scale, various pore filling mechanisms were found. For imbibition and drainage, cooperative filling occurs at large viscosity ratios. At low viscosity ratios, film flow (strong imbibition), and unstable bursts (strong drainage) were seen. Changes in pore filling mechanisms occurring at the same contact angle indicates the viscosity ratio impact on effective wettability variation.