Entrapping an impacting particle at a liquid–gasinterface
Entrapping an impacting particle at a liquid–gasinterface
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在液-气界面捕获撞击粒子
DOI：
10.1017/jfm.2018.134
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发表时间：
2018
影响因子：
3.7
通讯作者：
Hang Ding
中科院分区：
文献类型：
--
作者：
Han Chen;Hao Ran Liu;Xi Yun Lu;Hang Ding
我们通过数值研究导致撞击后球体被困在气液界面的机制。当撞击到液体池时，疏水球会遵循实验中确定的三种状态之一（Lee & Kim, Langmuir, vol. 24, 2008, pp. 142–145）：下沉、弹跳或被困在界面处。了解润湿性在流-结构与动态润湿相互作用的过程中的作用非常重要，特别是润湿性在多大程度上可以决定球体是否被截留在界面处。为此，数值模拟中采用了扩散界面浸入边界法。我们扩展了之前考虑的参数空间，提供了相图并确定了冲击动力学中的关键现象。然后，我们提出了尺度模型来解释球体截留发生的关键条件，并考虑了球体的润湿性。该模型显示出液滴的冲击惯性、表面张力、润湿性以及球体与液体的密度比之间良好的相关性。
We numerically investigate the mechanism leading to the entrapment of spheres at the gas–liquid interface after impact. Upon impact onto a liquid pool, a hydrophobic sphere is seen to follow one of the three regimes identified in the experiment (Lee & Kim, Langmuir, vol. 24, 2008, pp. 142–145): sinking, bouncing or being entrapped at the interface. It is important to understand the role of wettability in this process of flow–structure interaction with dynamic wetting, and in particular, to what extent the wettability can determine whether the sphere is entrapped at the interface. For this purpose, a diffuse-interface immersed boundary method is adopted in the numerical simulations. We expand the parameter space considered previously, provide the phase diagrams and identify the key phenomena in the impact dynamics. Then, we propose the scaling models to interpret the critical conditions for the occurrence of sphere entrapment, accounting for the wettability of the sphere. The models are shown to provide a good correlation among the impact inertia of the drop, the surface tension, the wettability and the density ratio of the sphere to the liquid.