Collapse dynamics of smectic-A bubbles
Collapse dynamics of smectic-A bubbles
复制标题
近晶A气泡的塌陷动力学
DOI：
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发表时间：
2006
期刊：
影响因子：
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通讯作者：
P. Oswald
中科院分区：
文献类型：
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作者：
F. Caillier;P. Oswald
摘要：从实验和理论上分析了近晶A型气泡的溃灭动力学。每个气泡从在中空圆柱体的端部拉伸的平膜膨胀，并通过毛细管的压力释放而放气。通过适当地选择毛细管的长度和内径，其总塌陷时间可在0.1s和20s之间变化。这个实验使我们能够表明，崩溃发生在两个步骤：最初的一个，持续几分之一秒，其中弯月面不稳定，并充满了焦点圆锥曲线，随后是一个更长的时间，在此期间，气泡崩溃，并与弯月面交换材料。通过同时测量气泡内的拉普拉斯压力和内部压力，我们能够充分表征弯月面内近晶相的剪切变稀行为。我们强调，这种方法是通用的，也可以适用于其他系统，如肥皂泡，条件是惯性效应可以忽略不计。
Abstract.The collapse dynamics of smectic-A bubbles are analyzed experimentally and theoretically. Each bubble is expanded from a flat film stretched at the end of a hollow cylinder and deflated through a pressure release by means of a capillary tube. Its total collapse time can be varied between 0.1s and 20s by suitably choosing the length and the internal diameter of the capillary. This experiment allowed us to show that the collapse takes place in two steps: an initial one, which lasts a fraction of a second, where the meniscus destabilizes and fills up with focal conics, followed by a much longer period during which the bubble collapses and exchanges material with the meniscus. By measuring simultaneously the Laplace pressure and the internal pressure inside the bubble, we were able to fully characterize the shear-thinning behavior of the smectic phase within the meniscus. We emphasize that this method is generic and could be applied as well to other systems such as soap bubbles, on condition that inertial effects are negligible.