Zhao Chuanning, Montazeri Kimia, Shao Bowen, Won Yoonjin
Mechanical and Aerospace Engineering Department, University of California, Irvine, California 92697, United States.
Langmuir. 2021 Aug 24;37(33):9964-9972. doi: 10.1021/acs.langmuir.1c00879. Epub 2021 Aug 11.
Droplet behaviors on solid surfaces will influence numerous droplet-based applications ranging from nonwetting-preferred water-repellent surfaces to wetting-preferred spray coatings. Understanding droplet behaviors is complicated and centered on integrating multiple parameters that include surface properties, droplet initial states, and other boundary conditions. Previous studies have observed that droplet impacting performance by showing their underlying mechanisms is sensitive to either droplet or surface boundary conditions. While the holistic view about droplet behaviors is still missing, here we study the droplet impacting and spreading behaviors by systemically varying surface conditions and droplet input parameters through the combination of optical experiments, simulations, and theoretical approaches. The observation defines three droplet behavior modes: , , and modes through their dynamic phases, where the most contributing parameters can be identified as the combination of initial Weber number and surface wettability. The We-θ phase diagram suggested here will provide a guideline for surface engineering with desired droplet dynamic behaviors.
液滴在固体表面的行为会影响众多基于液滴的应用，从偏好非润湿的疏水表面到偏好润湿的喷涂涂层。理解液滴行为很复杂，且集中于整合包括表面性质、液滴初始状态及其他边界条件在内的多个参数。先前的研究通过揭示其潜在机制观察到，液滴撞击性能对液滴或表面边界条件敏感。虽然关于液滴行为的整体观点仍缺失，但在此我们通过光学实验、模拟和理论方法相结合，系统地改变表面条件和液滴输入参数，来研究液滴撞击和铺展行为。该观察通过其动态阶段定义了三种液滴行为模式： 、 和 模式，其中最具影响力的参数可确定为初始韦伯数和表面润湿性的组合。此处提出的We-θ相图将为具有所需液滴动态行为的表面工程提供指导。
