Physique et Mécanique des Milieux Hétérogenes, CNRS, ESPCI Paris, Université PSL, Sorbonne Université, Université de Paris, F-75005 Paris, France;
Aix Marseille Université, CNRS, Centrale Marseille, Institut de Recherche sur les Phénomènes Hors Equilibre, 13013 Marseille, France.
Proc Natl Acad Sci U S A. 2020 Aug 25;117(34):20416-20422. doi: 10.1073/pnas.2007857117. Epub 2020 Aug 11.
Thin liquid or gas films are everywhere in nature, from foams to submillimetric bubbles at a free surface, and their rupture leaves a collection of small drops and bubbles. However, the mechanisms at play responsible for the bursting of these films is still in debate. The present study thus aims at understanding the drainage dynamics of the thin air film squeezed by gravity between a millimetric droplet and a smooth solid or a liquid thin film. Solving coupled lubrication equations and analyzing the dominant terms in the solid- and liquid-film cases, we explain why the drainage is much faster in the liquid-film case, leading often to a shorter coalescence time, as observed in recent experiments.
薄液膜或薄气膜在自然界中无处不在，从泡沫到自由表面的亚毫米气泡，它们的破裂会留下一小滴一小滴的液体和气泡。然而，导致这些薄膜破裂的机制仍存在争议。因此，本研究旨在理解在毫米级液滴和光滑固体或液体薄膜之间受重力挤压的薄空气膜的排液动力学。通过求解耦合的润滑方程，并分析固膜和液膜情况下的主导项，我们解释了为什么在液膜情况下排水速度更快，导致最近实验中观察到的聚结时间更短。
