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Three-dimensional shear in granular flow

Xiang Cheng·Jeremy B. Lechman·Antonio F. 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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Xiang Cheng, Jeremy B. Lechman, Antonio F. Barbero, Gary S. Grest, Heinrich M. Jaeger, Greg S. Karczmar, Matthias E. Möbius, Sidney R. Nagel. 2005-12-09. Three-dimensional shear in granular flow. https://doi.org/10.1103/physrevlett.96.038001

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