Multi-scale clustering in granular surface flows

D. Bonamy; F. Daviaud; L. Laurent; M. Bonetti; J. P. Bouchaud

doi:10.1103/physrevlett.89.034301

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arXiv · cond-mat/0109375

Multi-scale clustering in granular surface flows

D. Bonamy·F. Daviaud·L. Laurent·M. Bonetti·J. P. Bouchaud

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Abstract

We investigate steady granular surface flows in a rotating drum and demonstrate the existence of rigid clusters of grains embedded in the flowing layer. These clusters are fractal and their size is power-law distributed from the grain size scale up to the thickness of the flowing layer. The implications of the absence of a characteristic length scale on available theoretical models of dense granular flows are discussed. Finally, we suggest a possible explanation of the difference between velocity profiles observed in surface flows and in flows down a rough inclined plane.

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D. Bonamy, F. Daviaud, L. Laurent, M. Bonetti, J. P. Bouchaud. 2001-09-20. Multi-scale clustering in granular surface flows. https://doi.org/10.1103/physrevlett.89.034301

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