Eur. Phys. J. E (2006) 19: 17-22
https://doi.org/10.1140/epje/e2006-00006-7

Regular Articles

Drainage induced convection rolls in foams

I. Convective bubble motion in a tilted tube

School of Physics, Trinity College, Dublin, Ireland

^* e-mail: foams@aber.ac.uk

Received: 17 August 2005
Published online: 17 January 2006

Abstract

When liquid is added to a foam at sufficiently large flow rates, convective bubble motion will occur. Experiments are described in which the foam is confined in a tube which is tilted from the vertical. The theory of foam drainage is applied to this problem to show that the critical angle of tilt θ_c at which convection occurs is related to the liquid flow-rate Q by θ_c ∝Q^-3/4.