The merging of two fluid drops is one of the fundamental topological transitions occurring in free surface flow. Its description has many applications, for example, in the chemical industry (emulsions, sprays, etc.), in natural flows driving our climate, and for the sintering of materials. After the reconnection of two drops, strongly localized surface tension forces drive a singular flow, characterized by a connecting liquid bridge that grows according to scaling laws. We review theory, experiment, and simulation of the coalescence of two spherical drops for different parameters and in the presence of an outer fluid. We then generalize to other geometries, such as drops spreading on a substrate and in Hele–Shaw flow, and we discuss other types of mass transport, apart from viscous flow. Our focus is on times immediately after reconnection and on the limit of initially undeformed drops at rest relative to one another.

中文翻译：

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 聚结动力学


两个流体液滴的合并是自由表面流中发生的基本拓扑转变之一。它的描述有许多应用，例如，在化学工业（乳液、喷雾剂等）、驱动我们气候的自然流动以及材料烧结中。在两个液滴重新连接后，强局部表面张力驱动单一流动，其特征是根据缩放定律增长的连接液桥。我们回顾了在不同参数和存在外部流体的情况下两个球形液滴聚结的理论、实验和模拟。然后，我们推广到其他几何结构，例如在基板上扩散的液滴和 Hele-Shaw 流，并讨论了除粘性流之外的其他类型的质量传递。我们的重点是重新连接后的时间，以及最初未变形的液滴相对于彼此静止的极限。