Modelling, computation and analysis of droplets guided by Faraday waves: a complex system with macroscopic quantum analogies.

法拉第波引导的液滴的建模、计算和分析：具有宏观量子类比的复杂系统。

• 批准号: EP/N018176/1
• 负责人: Paul Milewski
• 金额: $ 40.38万
• 依托单位: University of Bath
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2016
• 资助国家: 英国
• 起止时间: 2016 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FN018176%2F1
• 关键词: Modelling; computation; analysis; droplets; guided

When a fluid filled container is shaken vertically, one may observe waves on the surface of that container if the shaking is sufficiently strong. These waves arise out of a subharmonic instability: they have half the frequency of the shaking, and are called Faraday waves.In separate experiments, high-speed films of droplet impacts on static fluid baths show that the droplet does not always coalesce with the bath on impact, but may bounce a few times before coalescing.Combining these two experimental facts, about 10 years ago it was discovered that millimetric liquid droplets can bounce indefinitely when dropped on the surface of a bath of the same liquid in a shaken container. The phenomenon occurs below the shaking threshold for the Faraday instability. More surprisingly, the droplets can also spontaneously "walk" along the surface of the vibrating bath. These walkers then exhibit many features previously thought to be exclusive to quantum mechanics such as wave-particle duality, quantised energy states, single particle diffraction and tunnelling behaviour.The aim of this proposal is to explore the fluid mechanical aspects of this system. There are many unanswered challenging questions due to the complexity of the problem. Fluid mechanics questions include the understanding of non coalescing drop impact, and the behaviour of reflecting walkers and their pilot wave field at walls. We will also seek to understand how a purely classical mechanics system exhibits quantum mechanical-like behaviour, and probe the limits of this analogy. The proposed research involves a combination of analytical and numerical approaches as well as comparisons with experiments. We will partner with an MIT state-of-the-art fluid dynamics laboratory which will provide both experimental data and design validation experiments. The problems we plan to study are of general interest in fluid mechanics and in the theory of free boundary problems and dynamical systems. It is expected that the results will have broad applications, in particular to the understanding of the impact of drops and particles with fluids.Faraday instabilities are also the most reliable way of generating consistently sized droplets continuously. Because of this there are several possible microfluidics applications for this research, such as developing better devices for delivering inhaled drugs.

当一个装满液体的容器垂直摇动时，如果摇动足够强烈，人们可以在该容器的表面观察到波浪。这些波由亚谐不稳定性产生：它们的频率是摇动频率的一半，被称为法拉第波。在单独的实验中，液滴撞击静态液浴的高速薄膜表明，液滴在撞击时并不总是与熔池结合，但在凝结之前可能会反弹几次。结合这两个实验事实，大约10年前，人们发现，毫米级的液滴在摇晃的容器中落在同一液体的浴缸表面时可以无限反弹。这种现象发生在法拉第不稳定性的抖动阈值以下。更令人惊讶的是，这些水滴还可以自发地沿着振动浴缸的表面行走。然后，这些步行器展示了许多以前被认为是量子力学独有的特征，如波粒二元性、量子能态、单粒子衍射和隧道行为。这项提议的目的是探索这个系统的流体力学方面。由于问题的复杂性，有许多悬而未决的挑战性问题。流体力学问题包括对非聚结液滴撞击的理解，以及反射步行者的行为和他们在墙壁上的导波波场。我们还将试图理解纯经典力学系统如何表现出类似量子力学的行为，并探索这种类比的局限性。拟议的研究包括分析和数值方法的结合以及与实验的比较。我们将与麻省理工学院最先进的流体动力学实验室合作，该实验室将提供实验数据和设计验证实验。我们计划研究的问题在流体力学、自由边界问题和动力系统理论中具有普遍意义。预计结果将有广泛的应用，特别是在理解液滴和粒子与流体的影响方面。法拉第不稳定性也是连续产生尺寸一致的液滴的最可靠的方法。正因为如此，这项研究有几种可能的微流控应用，例如开发更好的吸入药物输送设备。

项目成果

Introduction to focus issue on hydrodynamic quantum analogs.

介绍流体动力学量子类似物的焦点问题。

• DOI: 10.1063/1.5055383
• 发表时间: 2018
• 期刊: Chaos (Woodbury, N.Y.)
• 作者: Bush JWM

Capillary-scale solid rebounds: experiments, modelling and simulations

• DOI: 10.1017/jfm.2020.1135
• 发表时间: 2020-10
• 期刊: Journal of Fluid Mechanics
• 影响因子: 3.7
• 作者: Carlos A. Galeano-Rios;R. Cimpeanu;Isabelle A. Bauman;Annika MacEwen;P. Milewski;D. Harris

Faraday pilot-wave dynamics in a circular corral

圆形畜栏中的法拉第导波动力学

• DOI: 10.1017/jfm.2020.140
• 发表时间: 2020
• 期刊: Journal of Fluid Mechanics
• 影响因子: 3.7
• 作者: Durey M

Surface topography measurements of the bouncing droplet experiment

弹跳液滴实验的表面形貌测量

• DOI: 10.1007/s00348-016-2251-4
• 发表时间: 2016
• 期刊: Experiments in Fluids
• 影响因子: 2.4
• 作者: Damiano A

Non-wetting impact of a sphere onto a bath and its application to bouncing droplets

球体对浴的非润湿影响及其在弹跳液滴中的应用

• DOI: 10.1017/jfm.2017.424
• 发表时间: 2017
• 期刊: Journal of Fluid Mechanics
• 影响因子: 3.7
• 作者: Galeano-Rios C