Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
9675758 | Colloids and Surfaces A: Physicochemical and Engineering Aspects | 2005 | 7 Pages |
Abstract
Using high-frequency ultrasonic velocimetry, we perform simultaneously rheological and local velocity measurements in a 75%âwt. concentrated emulsion after a step-like shear rate applied for 3âh. Velocity profiles in the vicinity of the yield stress unveil the existence of transient inhomogeneous flows. However, approaching the equilibrium, banded states disappear and the emulsion flows homogeneously. At higher shear rates, we show that the local rheological behaviour evolves with the imposed shear rate. Changes in droplet concentration may be responsible for such a behaviour. We finally point out the presence of wall slip and investigate the evolution of the lubricating layers' thicknesses with the shear stress.
Related Topics
Physical Sciences and Engineering
Chemical Engineering
Colloid and Surface Chemistry
Authors
Lydiane Bécu, Pauline Grondin, Annie Colin, Sébastien Manneville,