Fundamentals and Applications of Liquid Drop Interactions with Complex Surfaces

液滴与复杂表面相互作用的基础和应用

• 批准号: RGPIN-2017-05636
• 负责人: Amirfazli, Alidad
• 金额: $ 5.1万
• 依托单位: York University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=711752
• 关键词: Fundamentals; Applications; Liquid; Drop; Interactions

The proposed research is a unique program that seeks to understand the behavior of complex surfaces and their interactions with liquid drops. Specifically, it will tackle areas of drop motion on a surface, fabrication of novel opto-fluidic devices based on liquid bridges, and drop impact onto complex (e.g. woven textile) surfaces. This research can produce the necessary knowledge to enable advanced technologies of strategic importance today, such as, energy systems (e.g. efficient condensers, and water management for fuel cells), protective textile and clothing, or biotechnology (e.g. accurate dispensing in PCR machines). A comprehensive study of incipient motion of sessile drop arrangements placed on a simple (smooth hydrophobic or hydrophilic), or a complex (patterned) surface exposed to a shearing airflow will be done. We will seek relations between drop properties, arrangement geometry and air velocity for incipient motion of drops on a surface. Through surface engineering strategies we seek to further assist the shedding of drops, by a shearing airflow, using patterned surfaces with hydrophobic and hydrophilic regions. Gaining fundamental knowledge about how to transfer liquids using a liquid bridge (e.g. used in dispensing and printing industries) is the key to advance such processes. We will study the complex case of bridges between non-parallel surfaces to understand the role of surface wettabilities, and dihedral angle between surfaces, in liquid transfer. In doing so we will consider liquid properties (surface tension, viscosity, etc.) and study both dynamic and quasi-static regimes. We have recently shown that by mechanically stimulating a liquid bridge, we can make a varifocal liquid lens; but to improve the response time of the lens, we will explore morphological changes of a liquid bridge under an electrical stress to develop novel optofluidic devices (e.g. a varifocal cylindrical lens). Simultaneous impact of multiple drops onto moving surfaces will be studied with the aim of understanding the impact morphology (e.g. splash limits, and resting drop shapes). Also, a systematic study of a single drop impact onto surfaces covered with a thin layer of an immiscible liquid will provide the fundamental information regarding the modes of drop-film interactions, e.g. film entrainment, bouncing, splashing, etc. A first comprehensive study of drop impact onto woven surfaces will allow determining the effectiveness of the claims made recently about protective nature of liquid infused or superhydrophobic textiles. This proposal, at its core, is designed to provide training for 20 students at different levels. They will gain skills needed for Canada's knowledge based economy by working on advanced imaging systems, surface fabrication and characterization, as well as analytical and modeling techniques. Communication skills will be honed through disseminating their findings.

拟议的研究是一个独特的程序，旨在了解复杂表面的行为及其与液滴的相互作用。具体而言，它将解决在表面上的下降运动区域，基于液体桥的新型光富集设备的制造，并在复合物（例如编织纺织品）表面上掉落冲击。这项研究可以产生必要的知识，以实现当今战略重要性的先进技术，例如能源系统（例如，有效的冷凝器和燃料电池的水管理），保护性纺织品和服装或生物技术（例如，在PCR机器中精确分配）。 将对将其在简单（光滑的疏水性或亲水性）或暴露于剪切气流的复杂（图案化的）表面上放置在简单的（光滑的疏水性或亲水性）上的无柄掉落排列的初期运动的全面研究。我们将寻求滴度性能，排列几何形状和空气速度之间的关系，以便在表面上滴的初期运动。通过表面工程策略，我们寻求使用具有疏水和亲水区域的图案表面，通过剪切气流进一步协助滴水。 获得有关如何使用液体桥（例如用于分配和印刷行业使用）转移液体的基本知识是推进此类过程的关键。我们将研究非平行表面之间的桥梁的复杂情况，以了解表面湿润性的作用，以及表面之间的二面角在液体转移中。在此过程中，我们将考虑液体特性（表面张力，粘度等），并研究动态和准静态状态。我们最近表明，通过机械刺激液体桥，我们可以制造一种变种液态镜头。但是，为了改善镜头的响应时间，我们将探索在电应力下液体桥的形态变化，以开发新型的光荧光设备（例如，变化圆柱晶状体）。 将研究多个液滴对移动表面的同时影响，以了解影响形态（例如，飞溅极限和静止下降形状）。此外，对单滴撞击在覆盖有薄层的不混溶液体覆盖的表面上的系统研究将提供有关滴膜相互作用模式的基本信息，例如膜的夹带，弹跳，飞溅等。首先对落下效果对编织表面的影响将允许确定最近关于液体注入或超疏水纺织品保护性的索赔的有效性。 该建议的核心旨在为20名不同级别的学生提供培训。他们将通过制定高级成像系统，表面制造和表征以及分析和建模技术来获得加拿大基于知识的经济所需的技能。沟通技巧将通过传播他们的发现来磨练。