Collaborative Research: CDS&E: Sculpting fluid flow using a programmed sequence of micro-pillars

合作研究：CDS&amp；E：使用编程的微柱序列雕刻流体流动spi (s) Ganapathysubramanian（爱荷华州立大学），DiCarlo（加州大学洛杉矶分校），Zola（罗格斯大学）控制流体流的形状和位置为创建结构化材料，制备生物样品和工程热量和质量传输提供了基本工具。操纵流体截面形状的方法侧重于通过流体扭转来制造混沌和混合，而不是用精确的流体扰动序列来排序或构造流。利用由简单微结构（如柱）序列引起的综合惯性流动变形来设计流体横截面形状的能力最近得到了证明。单柱作业的离散化以及它们的程序化叠加允许复杂流程程序的分层组装。尽管这种方法可以雕刻复杂的流体形状，但创建对实际应用很重要的用户定义的流动形状目前需要费力且耗时的反复试验和错误设计，并且通常无法在合理的时间范围内实现感兴趣的复杂流体形状。创建用户定义的流形状并自动确定产生该形状的柱序列的能力是一项重要而有影响力的进步，这是通过计算方法理想地解决的。这一挑战激发了CDS&amp；E项目的目标：(i)在计算上探索并创建一个以不同粒度级别注释的柱诱导转换库，以帮助使用并行CFD模拟进行计算选择。（ii）发展有效的计算方法来解决反问题，并为一组所需的流动变换选择柱序列。项目的这一部分将探索与解序列唯一性相关的数学和计算问题，处理大型柱转换库的可扩展方法，以及选择成本函数以实现有效解决设计问题。（iii）通过制造具有定义柱序列的微流体设计来测试计算框架和相关解决方案，以解决医学和材料中的三个变革性应用，包括制造定制的横截面聚合物纤维，以及在微通道表面捕获生物分子。引入一种对流体流编程的通用策略，将流体运动的非线性方程的复杂性从用户那里抽象出来，可以影响生物、化学和材料自动化，就像从计算机程序员那里抽象半导体物理学带来了计算革命一样。作为传播工作的一部分，将开发游戏和教育模块，包括沉浸式模拟和定向魔方类谜题，这将允许公众和感兴趣的各方尝试不同的支柱程序，并在游戏环境中学习流体力学及其应用。这些外联和劳动力发展活动将向社区强调计算在科学和技术中的关键作用。这种扩展将协同实现对细胞诊断、纳米材料制造和热冷却等应用产生重大影响的复杂流体转换的众包设计。

CBET 1306866/1307550/1307743Collaborative Research: CDS&E: Sculpting fluid flow using a programmed sequence of micro-pillarsPI(s) Ganapathysubramanian (Iowa State U.), DiCarlo (UCLA), Zola (Rutgers)Controlling the shape and location of a fluid stream provides a fundamental tool for creating structured materials, preparing biological samples, and engineering heat and mass transport. Methods to manipulate the cross-sectional shape of fluids have focused on creating chaos and mixing by fluid twisting instead of ordering or structuring streams with precise sequences of fluid perturbations. The ability to engineer the cross-sectional shape of a fluid using the integrated inertial flow deformations induced by sequences of simple microstructures (i.e. pillars) was recently demonstrated. Discretization of single pillar operations followed by their programmed superposition allows for the hierarchical assembly of complex flow programs. Although this approach has allowed for the sculpting of complex fluid shapes, creating user-defined flow shapes important for practical applications currently requires laborious and time-consuming trial and error design iterations, and often complex fluid shapes of interest are not achievable in a reasonable time frame. The ability to create a user-defined flow shape and automatically determine a sequence of pillars that yields this shape is a significant and impactful advance, which is ideally addressed by computational approaches. This challenge motivates the objectives of the CDS&E project: (i) Computationally explore and create a library of pillar-induced transformations annotated at different levels of granularity to aid in computational selection using parallel CFD simulations. (ii) Develop efficient computational methods to solve the inverse problem and select pillar sequences for a set of desired flow transformation. This part of the project will explore mathematical and computational issues related to uniqueness of solution sequences, scalable approaches to deal with the large libraries of pillar transformations, and choice of cost-functionals to enable efficient solution to the design problem. (iii) Test the computational framework and associated solutions by fabricating microfluidic designs with the defined pillar sequences that address three transformative applications in medicine and materials, including fabricating tailored cross-sectional polymer fibers, and capturing biomolecules on microchannel surfaces.The introduction of a general strategy to program fluid streams in which the complexity of the nonlinear equations of fluid motion are abstracted from the user can impact biological, chemical and materials automation in the same way that abstraction of semiconductor physics from computer programmers enabled a revolution in computation. As part of dissemination efforts, gaming and educational modules involving immersive simulations and directed rubix-cube like puzzles will be developed that will allow the public and interested parties to experiment with different pillar programs and learn about fluid mechanics and applications in a gaming environment. These outreach and workforce development activities will emphasize to the community the crucial role of computing in science and technology. This outreach will synergistically enable crowd-sourced design of complex flow transformations for applications that have a major impact on cell diagnostics, nano-materials fabrication, and thermal cooling.