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arXiv · 2202.10641

Viscous-inertial transition in dense granular suspension

Franco Tapia·Mie Ichihara·Olivier Pouliquen·Élisabeth Guazzelli
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Abstract

Granular suspensions present a transition from a Newtonian rheology in the Stokes limit to a Bagnoldian rheology when inertia is increased. A custom rheometer which can be run in a pressure or a volume-imposed mode is used to examine this transition in the dense regime close to jamming. By varying systematically the interstitial fluid, shear rate, and packing fraction in volume-imposed measurements, we show that the transition takes place at a Stokes number of 10 independent of the packing fraction. Using pressure-imposed rheometry, we investigate whether the inertial and viscous regimes can be unified as a function of a single dimensionless number based on stress additivity.

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Franco Tapia, Mie Ichihara, Olivier Pouliquen, Élisabeth Guazzelli. 2022-02-22. Viscous-inertial transition in dense granular suspension. https://doi.org/10.1103/physrevlett.129.078001

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