Couette flow of two-dimensional foams
Couette flow of two-dimensional foams
复制标题
二维泡沫的库埃特流动
DOI：
--
复制
发表时间：
2010
期刊：
影响因子：
--
通讯作者：
M. Hecke
中科院分区：
文献类型：
--
作者：
G. Katgert;B. Tighe;Matthias E. Möbius;M. Hecke
我们实验研究准二维无序泡沫库埃特几何形状的流动，无论是泡沫下的顶板和自由浮动的泡沫（气泡筏）挤压。在顶板的情况下，流动是强烈局部化的并且与速率相关。对于气泡筏的流动曲线变得基本上与速率无关，局部和全局流变学不匹配，并且特别是泡沫在应力低于全局屈服应力的区域中流动。我们将其归因于非局部效应，并表明Goyon等人最近引入的“流动性”模型（Nature，454（2008）84）捕获了有顶板和无顶板的流动的基本特征。
We experimentally investigate flow of quasi–two-dimensional disordered foams in Couette geometries, both for foams squeezed below a top plate and for freely floating foams (bubble rafts). With the top plate, the flows are strongly localized and rate dependent. For the bubble rafts the flow profiles become essentially rate independent, the local and global rheology do not match, and in particular the foam flows in regions where the stress is below the global yield stress. We attribute this to nonlocal effects and show that the “fluidity” model recently introduced by Goyon et al. (Nature, 454 (2008) 84) captures the essential features of flow both with and without a top plate.