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Shocks in sand flowing in a silo

Azadeh Samadani·L. Mahadevan·A. Kudrolli
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Abstract

We study the formation of shocks on the surface of a granular material draining through an orifice at the bottom of a quasi-two dimensional silo. At high flow rates, the surface is observed to deviate strongly from a smooth linear inclined profile giving way to a sharp discontinuity in the height of the surface near the bottom of the incline, the typical response of a choking flow such as encountered in a hydraulic jump in a Newtonian fluid like water. We present experimental results that characterize the conditions for the existence of such a jump, describe its structure and give an explanation for its occurrence.

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Azadeh Samadani, L. Mahadevan, A. Kudrolli. 2001-10-20. Shocks in sand flowing in a silo. https://doi.org/10.1017/s0022112001006991

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