CAREER: Dynamics of Confined Colloidal Suspensions

abstractcts - 0348175 j。Blawzdziewicz，耶鲁大学我职业发展计划的中心目标是建立一个强大的复杂流体研究项目，专注于宏观和粒子尺度的动力学现象。由于其技术的重要性（下文将讨论）和新的实验技术（光镊，扫描共聚焦显微镜）的发展，复杂流体动力学是一个迅速发展的领域。在我的小组中进行的研究将主要是理论和计算。然而，我计划与实验小组密切合作；我的一些项目已经建立了两个这样的合作关系。我的研究项目很好地结合了耶鲁大学机械工程系的总体需求，该部门旨在扩大其在胶体和复杂流体方面的项目。更广泛的影响我的研究项目的目标是提供对受限几何形状中胶体悬浮液动力学的基本理解。该项目为胶体系统的先进技术应用提供了基础，如利用胶体晶体制备光子频隙材料，设计新的微流体装置颗粒分选方法，开发高效的微过滤技术。我的职业发展计划中也有重要的教育成分。通过我小组的研究和我将教授的课程，我的研究生和本科生将了解在新兴技术中至关重要的物理现象。我还计划通过耶鲁大学科技前沿项目的一系列讲座来吸引高中生。我的目标是描述流体动力相互作用和结构力在由围壁或流体界面束缚的胶体悬浮液中的作用。当与约束几何相关的最小尺寸（例如，薄膜厚度）与颗粒尺寸相当时，流体动力和结构现象（例如，颗粒有序）的相互作用尤为明显。我建议在以下胶体系统中研究非平衡水动力和结构约束效应：在流体界面上吸附的颗粒，这些颗粒通常用于稳定或破坏乳液和泡沫。我们的目的是为单层吸附颗粒的动力学提供宏观描述，并根据颗粒尺度上的结构演变来评估相应的宏观输运系数。我们的目标是发展一种非平衡-热力学形式来描述这种薄膜逐步变薄的过程。研究有效热力学力的微观机制和相应的输运现象，并得到输运系数的定量结果。我们将研究被限制在与颗粒直径相当宽度的孔隙和微流控通道中的胶体颗粒的动力学。我们将探讨微观悬架结构与宏观横向运动的耦合。将发展变宽度孔隙中的悬浮动力学理论。我们将研究多颗粒流体动力相互作用对均匀和化学图案壁上颗粒沉积产生的胶体晶体结构的影响。通过施加气流将吸附颗粒从表面去除也将被研究。我的项目包括数值和理论的组成部分。为了执行所提出的数值研究，我们将开发快速的斯托克动力学算法，用于限制在平面或近平面表面的空间中的胶体悬浮液。我们提出的理论和数值方法的适用性将超越上面概述的研究问题。在未来的研究中，我们将使用这些方法来研究颗粒团簇之间的相互作用，过滤过程，热毛细现象和细菌运动。该项目也将为启动微孔吸附分子流体的新研究项目提供初步基础。

AbstractCTS-0348175J. Blawzdziewicz, Yale UniversityThe central goal of my career-development plan is to establish a strong complex-fluids research program focused on macroscopic and particle-scale dynamical phenomena. Due to its technological importance (discussed below) and development of new experimental techniques (optical tweezers, scanning confocal microscopy) the dynamics of complex fluids is a rapidly growing field. The research conducted in my group will be primarily theoretical and computational. However, I plan to have close collaborations with experimental groups; two such collaborations have already been established for some of my projects. My research program is well integrated with the overall needs of the Yale Mechanical Engineering Department which aims at expanding its program in colloids and complex fluids. Broader Impact The objective of my research project is to provide fundamental understanding of the dynamics of colloidal suspensions in confined geometries. This project provides a basis for advanced technological applications of colloidal systems, e.g., using colloidal crystals to producephotonic frequency-gap materials, designing new particle-fractionation methods for microfluidic devices, and development of efficient micro-filtration techniques. My career-development plan has also a significant educational component. Through research in my group and the courses I will teach, my graduate and undergraduate students will learn about physical phenomena that are crucial in emerging technologies. I also plan to reach high-school students through a series of lectures in a Frontiers of Science and Technology program at Yale.Intellectual Merit My goal is to describe the role of hydrodynamic interactions and structural forces in colloidal suspensions bounded by confining walls or fluid interfaces. The interplay of the hydrodynamic and structural phenomena (e.g., particle ordering) is particularly pronounced when the smallest dimension associated with the confinement geometry (e.g., film thickness) is comparable to the particle size. I propose investigations of nonequilibrium hydrodynamic and structural confinement effects in the following colloidal systems:Particles adsorbed at a fluid interface Such particles are often used to stabilize or destabilize emulsions and foams. Our aim is to provide a macroscopic description for the dynamics of a monolayer of adsorbed particles and to evaluate the corresponding macroscopic transport coefficients in terms of the structural evolution on the particle scale.Particle-stabilized thin liquid films Our goal is to develop a nonequilibrium-thermodynamicsformalism for description of the process of the stepwise thinning of such films. The microscopic mechanisms of the effective thermodynamic forces and the corresponding transport phenomena will be investigated, and quantitative results for the transport coefficients will be obtained.Colloidal suspensions in slit pores We will study the dynamics of colloidal particles confined in pores and microfluidic channels of the width comparable to the particle diameter. We will explore the coupling of the microscopic suspension structure with the macroscopic lateral motion. A theory for suspension dynamics in pores with varying width will be developed.Particle deposition on a planar wall We will investigate the effect of many-particle hydrodynamic interactions on the structure of colloidal crystals produced by particle deposition on uniform and chemically patterned walls. The removal of adsorbed particles from a surface by an applied flow will also be studied.My project involves numerical and theoretical components. To perform the proposed numerical investigations we will develop fast Stokesian-dynamics algorithms for colloidal suspensions confined in spaces bounded by planar or nearly-planar surfaces. The applicability of our proposed theoretical and numerical methods will go beyond the research problems outlined above. In future studies we will use these methods to study interactions between particle clusters, filtration processes, thermocapillary phenomena, and bacterial motions. The proposed project will also provide a preliminary basis for launching a new research program for molecular fluids adsorbed in micropores.