Generation of Motion of Drops with Interfacial Contact
Generation of Motion of Drops with Interfacial Contact
复制标题
DOI：
10.1021/la504925u
复制
发表时间：
2015-09-01
期刊：
影响因子：
3.9
通讯作者：
Daniel, Susan
中科院分区：
文献类型：
--
作者：
Chaudhury, Manoj K.;Chakrabarti, Aditi;Daniel, Susan
如果液滴受到润湿性或温度梯度的影响，则液滴会在固体表面上移动。然而，表面上表现为润湿滞后或一阶非线性摩擦的钉扎缺陷限制了运动，因为液滴必须超过临界尺寸才能移动。然而，滞后效应可以通过结构化或随机的外部振动来减轻，从而产生液滴的定向运动。许多众所周知的电子器件通用的整流、放大和开关功能都可以通过此类运动来设计。一个令人感兴趣的具体案例是表面上液滴的随机聚结，这会产生自生噪声。这种噪声克服了钉扎电位，从而产生聚结液滴的随机运动。当存在边界以通过吸收消除它们时，随机移动的聚结液滴本身表现出定向扩散通量。在存在偏压的情况下，聚结的液滴会执行扩散漂移运动，这可以在各种水和热管理技术中得到有用的应用。
A liquid drop moves on a solid surface if it is subjected to a gradient of wettability or temperature. However, the pinning defects on the surface manifested in terms of a wetting hysteresis, or first-order nonlinear friction, limit the motion in the sense that a critical size has to be exceeded for a drop to move. The effect of hysteresis can, however, be mitigated by an external vibration that can be either structured or stochastic, thereby creating a directed motion of the drop. Many of the well-known features of rectification, amplification, and switching that are generic to electronics can be engineered with such types of movements. A specific case of interest is the random coalescence of drops on a surface that gives rise to self-generated noise. This noise overcomes the pinning potential, thereby generating a random motion of the coalesced drops. Randomly moving coalesced drops themselves exhibit a directed diffusive flux when a boundary is present to eliminate them by absorption. With the presence of a bias, the coalesced drops execute a diffusive drift motion that can have useful applications in various water and thermal management technologies.