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Dense bubble flow in a silo: an unusual flow of a dispersed medium

Yann Bertho·Christophe Becco·Nicolas Vandewalle
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Abstract

The dense flow of air bubbles in a two-dimensional silo (through an aperture D) filled with a liquid is studied experimentally. A particle tracking technique has been used to bring out the main properties of the flow: displacements of the bubbles, transverse and axial velocities. The behavior of the air bubbles is observed to present similarities with non-deformable solid grains in a granular flow. Nevertheless, a correlation between the bubble velocities and their deformations has been evidenced. Moreover, a new discharge law (Beverloo-like) must be considered for such a system, where the flow rate is observed to vary as D^{1/2} and depends on the deformability of the particles.

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Yann Bertho, Christophe Becco, Nicolas Vandewalle. 2006-04-22. Dense bubble flow in a silo: an unusual flow of a dispersed medium. https://doi.org/10.1103/physreve.73.056309

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