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Three-dimensional shear in granular flow.

Xiang Cheng·Jeremy B Lechman·Antonio Fernandez-Barbero·Gary S Grest·Heinrich M Jaeger·Greg S Karczmar·Matthias E Möbius·Sidney R Nagel
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Abstract

The evolution of granular shear flow is investigated as a function of height in a split-bottom Couette cell. Using particle tracking, magnetic-resonance imaging, and large-scale simulations, we find a transition in the nature of the shear as a characteristic height H* is exceeded. Below H* there is a central stationary core; above H* we observe the onset of additional axial shear associated with torsional failure. Radial and axial shear profiles are qualitatively different: the radial extent is wide and increases with height, while the axial width remains narrow and fixed.

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ColloidsComputer SimulationMicrofluidicsModels, ChemicalMotionParticle SizeShear StrengthStress, MechanicalEvaluation StudyJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.

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Xiang Cheng, Jeremy B Lechman, Antonio Fernandez-Barbero, Gary S Grest, Heinrich M Jaeger, Greg S Karczmar, Matthias E Möbius, Sidney R Nagel. 2006-01-23. Three-dimensional shear in granular flow.. https://doi.org/10.1103/physrevlett.96.038001

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