Particle-induced miscible fingering: Continuum limit

Abstract

Oil is injected into a mixture of the same oil and noncolloidal particles inside a Hele-Shaw cell to investigate the connection between miscible fingering and the interfacial structure that develops inside the thin gap. By tuning the channel confinement relative to the particle size, it is demonstrated that shear-induced diffusion of particles can be enhanced and the interfacial shape caused to become more rounded, which results in changes in fingering morphologies. The results of the study suggest a potential use of the wall confinement to control hydrodynamic instabilities uniquely in suspensions.