论文标题
跌落形状在冲击和飞溅中的作用
The role of drop shape in impact and splash
论文作者
论文摘要
在许多重要领域,液滴对固体底物的影响和飞溅都是无处不在的。但是,先前的研究主要集中在球形下降上,而非球形情况(例如雨滴,带电的滴剂,振荡液滴和受电磁场影响的滴剂)仍然没有探索。使用铁氟烷,我们实现了各种滴形形状,并说明了形状在撞击和飞溅中的基本作用。实验表明,不同的下降形状在扩散动态,飞溅发作和飞溅量方面产生了较大的变化。但是,在所有这些变化的基础上,我们发现了各种滴形形状的通用机制:影响动力学受超级赛车模型的控制,飞溅开始是由开尔文·赫尔姆霍尔茨(Kelvin-Helmholtz)不稳定触发的,并且飞溅的量取决于液体散发前的能量耗散量。我们的研究概括了除球形几何形状以外的跌落影响研究,并揭示了使用滴度来控制撞击和飞溅的潜力。
The impact and splash of liquid drops on solid substrates are ubiquitous in many important fields. However, previous studies have mainly focused on spherical drops while the non-spherical situations, such as raindrops, charged drops, oscillating drops, and drops affected by electromagnetic field, remain largely unexplored. Using ferrofluid, we realize various drop shapes and illustrate the fundamental role of shape in impact and splash. Experiments show that different drop shapes produce large variations in spreading dynamics, splash onset, and splash amount. However, underlying all these variations we discover universal mechanisms across various drop shapes: the impact dynamics is governed by the superellipse model, the splash onset is triggered by the Kelvin-Helmholtz instability, and the amount of splash is determined by the energy dissipation before liquid taking off. Our study generalizes the drop impact research beyond the spherical geometry, and reveals the potential of using drop shape to control impact and splash.