CAREER: Investigating Fluid Surface Dynamics in Constrained Geometries

非技术摘要：当管道出现泄漏，或者雨滴在挡风玻璃上留下一条条水滴，或者啦啦队自发地聚集在一碗牛奶中时，我们每天都能看到液体表面动力学的例子。这项研究项目旨在通过开发一个实验实验室计划来探索和控制流体与固体表面之间的相互作用，以了解这些动力学和相关现象背后的基础科学。研究小组使用高倍显微镜、高速摄像和数字图像处理技术，捕捉到管道泄漏时表面张力、粘度和流速之间复杂的相互作用，液体在表面上分解成液滴，固体颗粒在液体表面形成图案并破碎。通过将实验观察、数据分析和理论结合起来，这项研究对日常现象的基本物理产生了新的见解，这些现象在一系列科学领域和行业中具有潜在的应用。该项目还具有重大的教育影响，为数十名本科生提供了在他们大学生涯的关键阶段直接从事尖端研究的机会。技术摘要：该研究计划调查几何约束-局部和全局-如何在两个主要背景下与流体表面及其不稳定性相互作用和改变。第一个目标是了解在部分润湿的稀薄流体“泄漏”中控制流动转变的基本物理，包括小溪破裂和流动启动和自发停止之间的振荡循环。第二个目标是探索从颗粒到大分子尺度的吸附物种在平坦和弯曲的流体表面上的毛细管驱动的相互作用、自发图案的形成和Marangoni驱动的表面破裂。研究团队使用成像、显微镜、高速摄像和数字图像分析来量化和了解定制桌面实验中的流体表面动力学。每个实验系统都被选为主要研究问题的关键方面的例证，由共同的实验技术和支配物理原理统一起来。通过专注于精心选择的互补系统中流体表面动力学和约束几何之间的相互作用，该研究计划揭示了对流体表面表面张力、曲率、流动、堵塞和破裂之间丰富的相互作用的新的、基本的见解。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Non-technical Abstract: When a pipe springs a leak, or raindrops leave streaks of droplets on a windshield, or Cheerios spontaneously clump together in a bowl of milk, we see everyday examples of the dynamics of fluid surfaces. This research project seeks to understand the fundamental science behind these dynamics and related phenomena by developing an experimental laboratory program for exploring and controlling the interactions between fluids and solid surfaces. Using high-magnification microscopes, high-speed videography, and digital image processing, the research team captures complex interactions between surface tension, viscosity, and flow speed as pipes leak, liquids break up into droplets on surfaces, and solid particles form patterns and shatter on the surfaces of fluids. By coupling the experimental observations, data analysis, and theory, this research yields novel insights into the fundamental physics of everyday phenomena that have potential applications in a range of scientific fields and industries. This project also has significant educational impact by affording dozens of undergraduate students opportunities to engage directly in cutting-edge research at a critical stage in their college careers.Technical Abstract:This research program investigates how geometric constraints—both local and global—interact with and change the dynamics of fluid surfaces and their instabilities in two main contexts. The first aim seeks to understand the fundamental physics that governs flow transitions in partially-wetting, thin fluid “leaks,” including rivulet breakup and oscillation cycles between flow start and spontaneous arrest. The second aim explores capillary-driven interactions, spontaneous pattern formation, and Marangoni-driven surface fracture on flat and curved fluid surfaces with adsorbed species from the granular to the macromolecular scale. The research team employs imaging, microscopy, and high-speed videography, and digital image analysis to quantify and understand fluid surface dynamics in custom built, tabletop experiments. Each experimental system is chosen to exemplify key aspects of the overarching research questions, unified by common experimental techniques and governing physical principles. By focusing on the interaction between fluid surface dynamics and constraining geometries in carefully chosen, complementary systems, this research program reveals new, fundamental insights into the rich interplay between surface tension, curvature, flow, jamming, and fracture on fluid surfaces.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.