From frictional to viscous behavior: three-dimensional imaging and rheology of gravitational suspensions
Joshua A Dijksman1, Elie Wandersman, Steven Slotterback
1Kamerlingh Onnes Lab, Universiteit Leiden, Postbus 9504, 2300 RA Leiden, The Netherlands.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|January 15, 2011
Abstract:
We probe the three-dimensional flow structure and rheology of gravitational (nondensity 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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