Brave new whorl: Vortex ring impingement on concave surfaces

勇敢的新螺纹：凹表面上的涡环冲击

• 批准号: 2211294
• 负责人: Byron Erath
• 金额: $ 31万
• 依托单位: Clarkson University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-04-01 至 2025-03-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2211294&HistoricalAwards=false
• 关键词: Brave; new; whorl; Vortex; ring

Vortex ring interactions with solid and deformable surfaces abound in nature and engineering flows. This situation is particularly relevant to the problem of replacement speech following a laryngectomy, where unsteady flow exiting a tracheoesophageal prosthesis produces pulsatile vortex rings that impinge on the curved wall of the esophagus. The resultant esophageal pressure field is responsible for successfully producing tracheoesophageal (i.e., replacement) speech. As such, understanding the mechanics that arise as vortex rings impact curved surfaces, in particular the pressure loading that is produced, could lead to improved success rates of replacement speech. This work is also more broadly applicable to both biological and engineering flows, such as cardiac hemodynamics, fluidic energy harvesting, wall-bounded turbulence, etc. The physics of these interactions will be investigated via flow visualization and both two-dimensional and tomographic particle image velocimetry. Acquisition of the velocity fields will enable determination of vorticity topologies, pressure field estimation, and identification of pressure source terms, as well as the resultant wall loading that arises during these interactions. This proposal blends the research efforts with a novel outreach plan to help high-school choral students envision how an interest in artistic expression in voice can lead to a career in science and engineering. The proposed work plan will explore the mechanics of vortex ring-surface interactions with both hemispherical and cylindrical cavities. Flow visualization and particle image velocimetry will be utilized to explore how a primary vortex ring approaching a cavity induces flow on the surface of the cavity, and subsequently causes the flow to separate and roll-up into a secondary vortex ring, and potentially develop azimuthal instabilities. This interaction will be investigated in both axisymmetric (hemispherical) and two-dimensional cavity geometries as a function of cavity radius relative to the primary vortex ring radius. The pressure loading that develops on the concave surface will also be quantified to provide insight into the fluid-structure interaction. The outcomes from this research plan will improve success rates of tracheoesophageal speech. The project will also facilitate the training and education of one graduate and multiple undergraduate students. Finally, the outreach program will inspire high-school students to pursue careers in science and engineering fields, while also providing paid summer research experiences for two of them.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.

自然界和工程流的涡流环与实心和可变形表面的相互作用遍布。这种情况尤其与喉切除术后替代语音的问题特别相关，在喉切除术后，不稳定的流动流动管道假体会产生脉动涡旋环，这些环在食管弯曲的壁上影响。最终的食管压力场负责成功产生气管食管（即替代）语音。因此，理解作为涡旋环的机制会影响弯曲表面，特别是产生的压力负载可能会提高替代语音的成功率。这项工作也更广泛地适用于生物学和工程流，例如心脏血液动力学，流体能量收集，壁构成的湍流等。这些相互作用的物理学将通过流动可视化和二维和层析成分粒子图像进行研究速度法。速度场的采集将确定涡度拓扑，压力场估计和压力源项的识别以及在这些相互作用期间产生的壁负荷。该建议将研究工作与一项新颖的外展计划融合在一起，以帮助高中合唱学生设想对语音中艺术表达的兴趣如何导致科学和工程学的职业。提出的工作计划将探索与半球形和圆柱腔的涡环相互作用的机制。流量可视化和粒子图像将使用速度计来探索如何接近空腔的主要涡流环在空腔表面上的流动，然后导致流动将流动分开并滚动成二级涡流环，并可能发展为Aiguthal的不稳定性。这种相互作用将在轴对称（半球）和二维空腔几何形状中进行研究，这是相对于原发性涡流环半径的腔半径的函数。在凹面表面上发育的压力负荷也将被量化，以洞悉流体结构相互作用。该研究计划的结果将提高气管食管语音的成功率。该项目还将促进一名研究生和多个本科生的培训和教育。最后，外展计划将激发高中生从事科学和工程领域的职业，同时还为其中的两个人提供了有偿的夏季研究经验。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的评估来支持的。智力优点和更广泛的影响审查标准。