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

Yann Bertho (1) , Christophe Becco (1) , Nicolas Vandewalle (1)

1 GRASP - Group for Research and Applications in Statistical Physics

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.

Mots clés: foam; silo; Beverloo; granular

Domaines: Matière Molle [cond-mat.soft]

Yann Bertho, Christophe Becco, Nicolas Vandewalle. Dense bubble flow in a silo: an unusual flow of a dispersed medium. Physical Review E : Statistical, Nonlinear, and Soft Matter Physics, 2006, 73, pp.056309. ⟨10.1103/PhysRevE.73.056309⟩. ⟨hal-00192126⟩