Thinning or thickening? Multiple rheological regimes in dense suspensions of soft particles

Abstract

The shear rheology of dense colloidal and granular suspensions is strongly nonlinear, as these materials exhibit shear-thinning and shear-thickening, depending on multiple physical parameters. We numerically study the rheology of a simple model of soft repulsive particles at large densities, and show that nonlinear flow curves reminiscent of experiments on real suspensions can be obtained. By using dimensional analysis and basic elements of kinetic theory, we rationalize these multiple rheological regimes and disentangle the relative impact of thermal fluctuations, glass and jamming transitions, inertia and particle softness on the flow curves. We characterize more specifically the shear-thickening regime and show that both particle softness and the emergence of a yield stress at the jamming transition compete with the inertial effects responsible for the observed thickening behaviour. This allows us to construct a dynamic state diagram, which can be used to analyze experiments.

6 pages, 3 figures

References in corpus (5)

• Theoretical perspective on the glass transition and amorphous materials
• Shear thickening of cornstarch suspensions as a re-entrant jamming transition
• Unified study of glass and jamming rheology in soft particle systems
• Shear thickening and migration in granular suspensions
• Compressing nearly hard sphere fluids increases glass fragility

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• Mean-field microrheology of a very soft colloidal suspension: inertia induces shear-thickening
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• Kinetic theory of discontinuous shear thickening of a moderately dense inertial suspension of frictionless soft particles
• Dynamic susceptibilities in dense soft athermal spheres under a finite-rate shear