Kerdraon Margaux, McGraw Joshua D, Dollet Benjamin, Jullien Marie-Caroline
Gulliver CNRS UMR 7083, PSL Research University, ESPCI Paris, 10 rue Vauquelin, 75005 Paris, France.
Université Grenoble Alpes, CNRS, LIPhy, 38000 Grenoble, France.
Phys Rev Lett. 2019 Jul 12;123(2):024501. doi: 10.1103/PhysRevLett.123.024501.
We report an experimental study concerning the capillary relaxation of a confined liquid droplet in a microscopic channel with a rectangular cross section. The confinement leads to a droplet that is extended along the direction normal to the cross section. These droplets, found in numerous microfluidic applications, are pinched into a peanutlike shape thanks to a localized, reversible deformation of the channel. Once the channel deformation is released, the droplet relaxes back to a pluglike shape. During this relaxation, the liquid contained in the central pocket drains towards the extremities of the droplet. Modeling such viscocapillary droplet relaxation requires considering the problem as 3D due to confinement. This 3D consideration yields a scaling model incorporating dominant dissipation within the droplet menisci. As such, the self-similar droplet dynamics is fully captured.
我们报告了一项关于在具有矩形横截面的微观通道中受限液滴的毛细管松弛的实验研究。这种限制导致液滴在垂直于横截面的方向上伸展。在许多微流体应用中发现的这些液滴，由于通道的局部可逆变形而被挤压成花生状。一旦通道变形解除，液滴就会松弛回塞状。在这种松弛过程中，中央口袋中的液体流向液滴的两端。由于限制，对这种粘性毛细管液滴松弛进行建模需要将问题视为三维问题。这种三维考虑产生了一个包含液滴弯月面内主要耗散的标度模型。因此，完全捕捉到了自相似的液滴动力学。
