CAREER: Morphing Surfaces for Flow Control

职业：用于流量控制的变形表面

• 批准号: 0747672
• 负责人: Beverley McKeon
• 金额: $ 40万
• 依托单位: California Institute of Technology
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-03-15 至 2013-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0747672&HistoricalAwards=false
• 关键词: CAREER; Morphing; Surfaces; Flow; Control

CBET-0747672McKeonThis integrated research and education study investigates the physics associated with the interaction of boundary layer flows with morphing surfaces (defined here as thin skins capable of generating small, distributed or discrete, morphological or geometrical perturbations to the wall boundary condition). Fundamental questions to be addressed include how well can the characteristics of a boundary layer be manipulated via a morphing surface, what additional fundamental understanding of fluid physics can be gained from this new means of activation and how should graduate students best be prepared for this interdisciplinary research? An interdisciplinary approach will focus on: identification of the flow physics in new regimes that can now be interrogated using active materials; in situ characterization of the interaction between boundary layer flows and morphing surfaces; and investigation of open-loop actuation using surface morphing as a precursor to closed-loop control. Arrays of individually-addressable micro- or nano- actuators will be replaced with a coherent surface, or "skin" capable of either morphological changes or small adaptation of local geometry. Activation of properly designed morphing surfaces represents minimal control effort, with the potential for relatively simpler models relating the input to resultant structural changes in the flow. This research will expand our understanding of flow physics in receptive flows into a parameter range not previously accessible, or perhaps imaginable, before the advent of some newer materials. Classical hypotheses can then be revisited for canonical flows after the introduction of time-dependent wall motion and providing potential means for actuation for future closed-loop control work. Experiments on morphing surfaces also promise further insight into fundamental questions concerning a statically rough wall, mixing and vorticity flux in boundary layers. Broader impacts address environmental concerns and expanded air vehicle performance using active control or optimization of vehicular boundary layers via artificial manipulation of the boundary layer structure. This research will show how this could be achieved without large weight or structural penalties, and ultimately leading to a design feature for new vehicles. Collaborations with the active materials industry and a leading controls researcher seek to unite multiple fields to address this highly interdisciplinary topic. The educational goal is to develop a synergistic training scheme in flow control, suitable for addressing the research described here and educating graduate researchers to inhabit the middle ground between traditional disciplines associated with flow control, including fluid mechanics, control, dynamics and solid mechanics. This will culminate with a graduate level course designed to unify experimental, computational and modeling approaches to tackle advanced flow control problems. Outreach will target general public interest in fluid dynamics, with emphasis on girls of high school age and a continuing commitment to undergraduate research participation.

CBET-0747672McKeon这项综合研究和教育研究研究了与边界层流与变形表面（此处定义为能够对壁边界条件产生小的、分布式或离散的形态或几何扰动的薄皮）相互作用相关的物理现象。需要解决的基本问题包括如何通过变形表面操纵边界层的特性，从这种新的激活方法中可以获得对流体物理学的哪些额外的基本理解，以及研究生应该如何为这项跨学科研究做好最好的准备？跨学科方法将侧重于： 识别新机制中的流动物理学，现在可以使用活性材料进行询问；边界层流和变形表面之间相互作用的原位表征；以及使用表面变形作为闭环控制先驱的开环驱动研究。可单独寻址的微米或纳米致动器阵列将被一致的表面或能够发生形态变化或局部几何形状小幅适应的“皮肤”所取代。激活正确设计的变形表面意味着最小的控制工作量，并且有可能建立相对更简单的模型，将输入与流动中产生的结构变化相关联。这项研究将扩大我们对接收流中流动物理的理解，使其达到在一些新材料出现之前无法获得或无法想象的参数范围。在引入随时间变化的壁运动并为未来闭环控制工作提供潜在的驱动手段后，可以重新审视经典假设以实现规范流动。变形表面的实验也有望进一步深入了解有关静态粗糙壁、边界层中的混合和涡通量的基本问题。更广泛的影响通过人工操纵边界层结构来主动控制或优化飞行器边界层，解决环境问题并扩展飞行器性能。这项研究将展示如何在不增加重量或结构损失的情况下实现这一目标，并最终实现新车的设计功能。与活性材料行业和领先的控制研究人员的合作寻求联合多个领域来解决这个高度跨学科的主题。教育目标是制定流量控制方面的协同培训计划，适合解决此处描述的研究，并教育研究生研究人员处于与流量控制相关的传统学科（包括流体力学、控制、动力学和固体力学）之间的中间地带。这将以研究生水平课程结束，该课程旨在统一实验、计算和建模方法来解决高级流量控制问题。外展活动将针对公众对流体动力学的兴趣，重点关注高中年龄段的女孩，并持续致力于本科生研究参与。