Collaborative Research: Manipulation of Suspended Microparticles via Localized Fluid Boundary Dynamics: Modeling, Simulation, and Experiments

合作研究：通过局部流体边界动力学操纵悬浮微粒：建模、模拟和实验

• 批准号: 0969869
• 负责人: Jeff Eldredge
• 金额: $ 20.2万
• 依托单位: University of California-Los Angeles
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-07-01 至 2014-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0969869&HistoricalAwards=false
• 关键词: Collaborative; Research; Manipulation; Suspended; Microparticles

This project will advance a novel, biologically inspired method for the manipulation of solid particles suspended in fluids on a microscopic scale through complementary theoretical, computational, and experimental research. A comprehensive mathematical framework will be developed for describing the control of fluid flows at low Reynolds number through localized cyclic boundary deformations using concepts from differential geometry and dynamical systems theory. A high-fidelity numerical approach will be developed for simulating such problems using a viscous vortex particle method. A pair of experimental platforms on contrasting physical scales will be constructed, each comprising a system of reconfigurable resonant probes mimicking cilia observed in nature, and extensive data will be collected to calibrate both theoretical and computational models. Algorithmic methods for separating and sorting particles, and for tailoring the spatial trajectories of individual particles, will be devised and demonstrated experimentally. The project focuses on developing and demonstrating a novel technique for separating and manipulating fragile microscopic objects immersed in fluids, which has a growing list of applications ranging from the mechanical testing of macromolecules like DNA to the assisted fertilization of human ova with immotile sperm to the sustained excitation of fluid-borne abrasive particles for the precision machining of brittle surfaces. Models will be developed to predict the trajectories of particles in fluids containing multiple vortex fields. These vortex fields will be produced experimentally using oscillating fibers. A pair of experimental platforms with millimeter and micrometer (1/1000 of a millimeter) physical scales will be constructed. For each platform, a system of reconfigurable resonant probes will be used to generate steady vortex fields in particle-bearing fluids. The smallest probes will mimic the microscopic oscillating cilia observed in nature. Data will be collected to validate the theoretical and computational predictive models. This project will not only engender integrated advancements in applied mathematics, computational science, and engineering, but will also shed light on the physics underlying a physiological design present in protozoa and humans alike. The micromanipulation method to be developed represents an improvement over alternative technologies in simplicity, portability, and cost. The PIs' plan for developing this method incorporates a multi-institutional collaboration involving the directed mentoring of at least one postdoctoral researcher, at least two PhD students, and a number of undergraduates (with a deliberate eye toward promoting diversity), the curricular expansion of two cross-disciplinary graduate courses and two undergraduate courses at the PIs' universities, and outreach to biology students at a third university and to high school students in an ethnically diverse area.

该项目将通过互补的理论、计算和实验研究，推进一种新颖的、受生物学启发的方法，用于在微观尺度上操纵悬浮在流体中的固体颗粒。一个全面的数学框架将开发描述控制流体流动在低雷诺数通过局部循环边界变形使用微分几何和动力系统理论的概念。本文将发展一种高保真的数值方法，利用粘性涡旋粒子法来模拟这类问题。将在不同的物理尺度上构建一对实验平台，每个平台都包括一个可重构的共振探针系统，模拟自然界中观察到的纤毛，并将收集大量数据来校准理论和计算模型。分离和分类粒子的算法方法，以及裁剪单个粒子的空间轨迹，将被设计和实验证明。该项目的重点是开发和展示一种分离和操纵浸泡在流体中的脆弱微观物体的新技术，该技术的应用范围越来越广，从DNA等大分子的机械测试，到用不动的精子辅助人类卵子受精，再到为脆性表面的精密加工而持续激发流体传播的磨料颗粒。将开发模型来预测含有多个涡旋场的流体中粒子的轨迹。这些涡旋场将在实验中使用振荡纤维产生。将建造一对毫米和微米（1/1000毫米）物理尺度的实验平台。对于每个平台，一个可重构谐振探头系统将用于在含粒子流体中产生稳定的涡流场。最小的探针将模仿自然界中观察到的微小的振荡纤毛。将收集数据来验证理论和计算预测模型。这个项目不仅将带来应用数学、计算科学和工程学的综合进步，而且还将阐明原生动物和人类的生理设计背后的物理学。待开发的微操作方法在简单性、可移植性和成本方面比其他技术有了改进。ppi开发这种方法的计划包括多机构合作，包括至少一名博士后研究员、至少两名博士生和一些本科生（有意促进多样性）的直接指导，以及在ppi所在大学扩展两门跨学科研究生课程和两门本科课程。并向第三所大学的生物系学生和一个种族多元化地区的高中生提供服务。