UNS: The Interaction of Coherent Structures in a Shear Layer with a Flexible Beam

UNS：剪切层中相干结构与柔性梁的相互作用

• 批准号: 1511761
• 负责人: Byron Erath
• 金额: $ 28万
• 依托单位: Clarkson University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-08-01 至 2019-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1511761&HistoricalAwards=false
• 关键词: UNS; Interaction; Coherent; Structures; Shear

1511761(Erath)The goal of this proposal is to investigate experimentally and numerically the fluid structure interaction when fluid passes around a flexible beam. This is a representative model of air flow past the vocal cords. The study will focus not only on conditions representing healthy vocal cords, but mainly on cases where the vocal cords are not healthy. Results from the proposed research can, thus, impact speech rehabilitation and could be felt by many people among the roughly 30% of the population of the US, who are estimated to suffer voice pathology at some point in their lives.The main objective of the proposed research is to identify the mechanisms by which a train of vortices advecting over a flexible beam incite motion in the structure, and parametrically explore this fundamental fluid- structure interaction problem. It is proposed to quantify how vortices produced during speech impact vocal fold dynamics in both normal, as well as pathological speech. Currently, there is incomplete understanding of the interplay between the aerodynamic loading as air comes to the vocal cords and the structural response of the tissue. This deficiency will be addressed by experimentally and theoretically/numerically investigating vortex-beam interactions that arise from coherent structures passing over a flexible beam. The hypothesis is that the coherent vortical structures are formed from the Kelvin-Helmholtz instability in the shear layer of the flow. The excitation of the beam will be investigated over a range of nondimensional beam, fluid, and geometrical parameters. The experimental results will validate the theoretical flow model of vortex-beam interactions, which will then be used to extend and explore the parameter space beyond the limitations of the experimental facility. The theoretical model will ultimately be applied to a numerical model of voiced speech to quantify the role of vortex-tissue interactions on vocal outcomes. The fundamental problem of vortices interacting with a deformable surface also has specific relevance to the topic of using deformable electroactive devices to harvest energy from fluids. In addition to graduate and undergraduate student education, a plan for K-12 outreach is proposed, where the PI will partner with high school choir directors to provide classroom demonstrations relating voice and singing to science.

1511761（ERATH）该提案的目的是在流体围绕柔性束围绕流体时进行实验和数值研究。这是经过声带的代表性模型。该研究不仅将重点放在代表健康声带的条件上，而且主要是在声带不健康的情况下。因此，拟议的研究的结果可能会影响言语康复，并且在美国大约30％的人口中，许多人都可以感受到他们的生活，据估计，他们在生活中的某个时候会遭受语音病理的影响。拟议的研究是确定旋转旋转的旋转轨道上的机制，而涡流促进了结构中的运动，并参数探索了这种基本的流体结构相互作用问题。 提议量化在语音和病理性语音中语音上产生的涡流影响声音动态的方式。当前，由于空气加入声带和组织的结构反应，对空气动力学负荷之间的相互作用有不完全的了解。这种缺陷将通过实验和理论/数值研究涡流相互作用来解决，这些相互作用是由经过柔性束的相干结构引起的。假设是，相干涡度结构是由剪切层在流动层中的开尔文 - 霍尔莫尔兹不稳定性形成的。光束的激发将在一系列非二维光束，流体和几何参数上进行研究。实验结果将验证涡流相互作用的理论流模型，然后将其用于扩展和探索参数空间，超出实验设施的局限性。理论模型最终将应用于语音语音的数值模型，以量化涡流 - 组织相互作用在人声结果上的作用。与可变形表面相互作用的涡流的基本问题也与使用可变形的电活性设备从流体中收集能量的主题具有特定的相关性。除了研究生和本科生教育外，还提出了K-12宣传计划，PI将与高中合唱团主管合作，提供有关语音和唱歌与科学的教室示范。