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Transverse Instability of Avalanches in Granular Flows down Incline

Igor S. Aranson·Florent Malloggi·Eric Clement
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Abstract

Avalanche experiments on an erodible substrate are treated in the framework of ``partial fluidization'' model of dense granular flows. The model identifies a family of propagating soliton-like avalanches with shape and velocity controlled by the inclination angle and the depth of substrate. At high inclination angles the solitons display a transverse instability, followed by coarsening and fingering similar to recent experimental observation. A primary cause for the transverse instability is directly related to the dependence of soliton velocity on the granular mass trapped in the avalanche.

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Igor S. Aranson, Florent Malloggi, Eric Clement. 2005-10-04. Transverse Instability of Avalanches in Granular Flows down Incline. https://doi.org/10.1103/physreve.73.050302

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