FLUID DYNAMICS OF RIVULET FLOW BETWEEN PLATES

W. DRENCKHAN; H. RITACCO; A. SAINT-JALMES; A. SAUGEY; P. MACGUINNESS; A. VAN DER NET; D. LANGEVIN; D. WEAIRE

PHYSICS OF FLUIDS

AMERICAN INSTITUTE OF PHYSICS

Año: 2007 vol. 19 p. 1021011 - 10210112

1070-6631

We present computational and experimental investigations into the fluid dynamics of a narrow stream of surfactant solutions, which descends under gravity between two narrowly spaced, vertical glass plates. Such a “rivulet” is bounded by two liquid/solid and two  mobile liquid/gas interfaces, posing fluid dynamic problems of direct relevance to local fluid flow in liquid foams and recently reported meandering phenomena. The rivulet presents a system in which the coupling between the bulk flow and the rheological properties of the gas/liquid interface can be systematically investigated. In particular, it carries the promise of providing an alternative measuring  technique for interfacial shear viscosities. We present finite element simulations in conjunction with experiments in order to describe the relationship between the rivulet geometry, the flow field, and the interfacial shear viscosities. We also report on the role of the boundary condition between the liquid-carrying channels surface Plateau borders and the thin soap film, which spans the two plates at low flow rates.