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arXiv · 2409.01297

Rheological regimes in agitated granular media under shear

Olfa D'Angelo·Matthias Sperl·W. Till Kranz
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Abstract

Agitated granular media have a rich rheology: they exhibit Newtonian behavior at low shear rate and density, develop a yield stress at high density, and cross over to Bagnoldian shear thickening when sheared rapidly -- making them challenging to encompass in one theoretical framework. We measure the rheology of air-fluidized glass particles, spanning five orders of magnitude in shear rate. By comparing fluidization-induced to Brownian agitation, we show that all rheological regimes can be delineated by two dimensionless numbers -- the Peclet number, $\Pe$, and the ratio of shear-to-fluidization power, $\Pi$ -- and propose a constitutive relation that captures all flow behaviors, qualitatively and quantitatively, in one unified framework.

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Olfa D'Angelo, Matthias Sperl, W. Till Kranz. 2024-09-02. Rheological regimes in agitated granular media under shear. https://doi.org/10.1103/physrevlett.134.148202

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