EAGER: Numerical and Experimental Study of Purcell-Like Locomotion for Microswimmers

EAGER：微型游泳者类普塞尔运动的数值和实验研究

• 批准号: 2328027
• 负责人: Mingjun Wei
• 金额: $ 18.09万
• 依托单位: Kansas State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-06-15 至 2025-05-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2328027&HistoricalAwards=false
• 关键词: EAGER; Numerical; Experimental; Study; Purcell

Untethered microswimmers have attracted many interests in recent years due to their great potential in various applications such as minimally invasive medicine and active environment monitoring. One of the most famous locomotion by micro-swimmers is the so-called “Purcell swimmer” which was first proposed by and later named after Nobel laureate Edward Purcell. The Purcell swimmer geometrically presents the simplest segmented structure for one-dimensional locomotion on microscale where the Reynolds number is small. Earlier numerical and theoretical studies were universally based on the same assumption of Stokes flow, which neglects the nonlinear and inertial contributions. However, under a more careful examination, actual flow conditions of many microswimmers do not satisfy the criterion to ignore those contributions. On the other hand, experimental demonstrations of untethered Purcell swimmers and associated flow dynamics were scarce due to the challenge of implementing individually-driven hinges in a non-invasive manner with existing fabrication methods for microscale. The success of this study will broaden the understanding of flow physics in micro-swimmers and experimentally demonstrate a new approach to fabricate and control untethered micro-swimmers for the study of their locomotion and flow dynamics. Education components such as graduate education and class teaching are integrated in this project. Demonstration of microswimmer locomotion is included in outreach events to promote public interests in STEM. There are two main goals in this research. First, a unique electromicrofluidic printing technique will position and assemble multiple droplets containing cross-linkable prepolymers and particle embedded hydrogels to fabricate micro-swimmers with individually driven hinges, thus it will allow to manufacture and optically drive untethered Purcell swimmers for the first time. Second, high-fidelity numerical simulation solving Navier-Stokes equations will be used to study Purcell-like locomotion of micro-swimmers to exam the nonlinear and inertial impact on the involved flow physics at the Reynolds number of interests. Both parts of the research involve the study of a newly proposed X-swimmer as a micro-swimmer capable of three-dimensional Purcell-like locomotion. The outcome of this study for three-dimensional locomotion will change the scope of Purcell-like locomotion and enable new possibilities in the study of microswimmer locomotion and flow dynamics. The success of the proposed research will lead to future interdisciplinary collaborations in a broader community for research in micro-swimmers and their various applications.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.

近年来，无系绳微型游泳器因其在微创医学和主动环境监测等各种应用中的巨大潜力而​​引起了许多人的兴趣，微型游泳器最著名的运动之一是首次提出的所谓“Purcell游泳器”。由诺贝尔奖获得者爱德华·珀塞尔（Edward Purcell）提出并以他的名字命名。珀塞尔游泳者在几何上提出了雷诺数很小的微尺度一维运动的最简单分段结构。普遍基于相同的斯托克斯流假设，忽略了非线性和惯性贡献。然而，在更仔细的检查下，许多微型游泳器的实际流动条件不满足忽略这些贡献的标准。由于用现有的微尺度制造方法以非侵入性方式实现单独驱动的铰链的挑战，不受束缚的珀塞尔游泳者和相关的流动动力学的研究很少。这项研究的成功将拓宽对流动物理学的理解。微型游泳者并通过实验展示了一种制造和控制不受束缚的微型游泳者的新方法，用于研究其运动和流动动力学。该项目包括研究生教育和课堂教学等教育内容。这项研究有两个主要目标：首先，独特的电微流体打印技术将定位和组装包含可交联预聚物和颗粒的多个液滴。嵌入水凝胶来制造具有单独驱动铰链的微型游泳者，因此它将首次允许制造和光学驱动不受束缚的珀塞尔游泳者。其次，高保真数值模拟求解纳维-斯托克斯方程将用于研究类似珀塞尔的运动。研究的两部分都涉及对新提出的 X 游泳器的研究。能够进行类珀塞尔运动的微型游泳者这项关于三维运动的研究成果将改变类珀塞尔运动的范围，并为微型游泳者运动和流动动力学的研究带来新的可能性。拟议的研究将导致未来在更广泛的社区中进行跨学科合作，以研究微型游泳者及其各种应用。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力评估进行评估，被认为值得支持优点和更广泛的影响审查标准。