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，例如化学工业（乳液、喷雾等）、驱动气候的自然流动以及材料的烧结。两个液滴重新连接后，强烈的局部表面张力驱动奇异流，其特征是连接液桥根据缩放定律增长。我们回顾了不同参数和存在外部流体的情况下两个球形液滴合并的理论、实验和模拟。然后，我们推广到其他几何形状，例如在基底上扩散的液滴和赫勒-肖流，并且我们讨论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立即发生的时间以及最初未变形的静止液滴相对于彼此的极限。