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arXiv · 1004.1121

From Frictional to Viscous Behavior: Three Dimensional Imaging and Rheology of Gravitational Suspensions

Joshua A. Dijksman·Elie Wandersman·Steven Slotterback·Christian R. Berardi·William Derek Updegraff·Martin van Hecke·Wolfgang Losert
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Abstract

We probe the three dimensional flow structure and rheology of gravitational (non-density matched) suspensions for a range of driving rates in a split-bottom geometry. We establish that for sufficiently slow flows, the suspension flows as if it were a dry granular medium, and confirm recent theoretical modeling on the rheology of split-bottom flows. For faster driving, the flow behavior is shown to be consistent with the rheological behavior predicted by the recently developed "inertial number approaches for suspension flows.

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Joshua A. Dijksman, Elie Wandersman, Steven Slotterback, Christian R. Berardi, William Derek Updegraff, Martin van Hecke, Wolfgang Losert. 2010-04-07. From Frictional to Viscous Behavior: Three Dimensional Imaging and Rheology of Gravitational Suspensions. https://doi.org/10.1103/physreve.82.060301

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