How does a concentrated emulsion flow?: Yielding, local rheology, and wall slip

被引：47

作者：

Bécu, L ^{[1
]}

Grondin, P ^{[1
]}

Colin, A ^{[1
]}

Manneville, S ^{[1
]}

机构：

[1] Ctr Rech Paul Pascal, F-33600 Pessac, France

来源：

COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS | 2005年 / 263卷 / 1-3期

关键词：

emulsion flow; local rheology; wall slip;

D O I：

10.1016/j.colsurfa.2004.12.033

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

Using high-frequency ultrasonic velocimetry, we perform simultaneously rheological and local velocity measurements in a 75% wt. concentrated emulsion after a step-like shear rate applied for 3h. 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. (c) 2004 Published by Elsevier B.V.

引用

页码：146 / 152

页数：7

共 10 条

[1] RHEOLOGY OF EMULSIONS - A REVIEW [J].