Development of an Asymptotically-Reduced, Multiscale Model of Turbulent Boundary Layer Dynamics at Extreme Reynolds Numbers

极限雷诺数下湍流边界层动力学的渐近简化多尺度模型的开发

• 批准号: 1437851
• 负责人: Gregory Chini
• 金额: $ 41万
• 依托单位: University of New Hampshire
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-07-15 至 2019-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1437851&HistoricalAwards=false
• 关键词: Development; Asymptotically; Reduced; Multiscale; Model

1437851Chini, Gregory The goal of the proposed study is to use a combination of theory and unique experiments to develop a new approach to modeling turbulent flows in the boundary layer. The capacity to understand, predict, and control turbulent boundary layer dynamics is important for a multitude of technological applications and scientifically important processes. Turbulence is prevalent in the world we live in and in the industry. Success in this research could impact any industrial process that involves turbulent flow, with consequent societal benefits in the form of new products, improved energy efficiency, quieter systems, etc. Problems related to geophysical and astrophysical flows could also be approached in a new, more accurate way. The educational plan involves the participation of both graduate and undergraduate students.The main goal of the proposed research is to develop a multiscale Partial Differential Equation (PDE) model of turbulent boundary layer dynamics through the integrated useof high Reynolds number (Re) asymptotics and well-resolved high-Re experiments. By its very nature, the model development process will elucidate the so-called "inner/outer" interaction, as these are linked to boundary layer evolution as Re tends to infinity. In addition, numerical solutions of the multiscale PDEs promise to be less costly than direct numerical simulations (DNS) of the primitive Navier?Stokes (NS) equations from which they are derived, thereby enabling simulations in otherwise inaccessible parameter regimes. The proposed model will be distinct from other recent efforts, because the model retains a first principles foundation, with no reliance on system inputs or phenomenological assumptions. The multiscale analysis on which the model is based brings together recent advances in the asymptotic analysis of turbulent geophysical flows, of "exact coherent structures" in high-Re shear flows, and of the mean dynamics in canonical turbulent wall-flows. The target model is a closed multiscale PDE system that is self-consistently and systematically simplified relative to the primitive NS equations. This critical scaling information is only accessible through well-resolved, high-Re experiments. In this regard, the Univ. of New Hampshire Flow Physics Facility (FPF), which is the world's largest flow physics quality boundary layer wind tunnel, allows high-resolution measurements of velocity and vorticity at extreme Reynolds numbers.

1437851CHINI，GREGORY拟议的研究的目标是使用理论和独特的实验的组合来开发一种新的方法来建模边界层中的湍流。理解，预测和控制湍流边界层动态的能力对于多种技术应用和科学重要的过程很重要。在我们生活在该行业中的世界中，湍流普遍存在。这项研究的成功可能会影响任何涉及动荡流的工业过程，因此以新产品形式，提高能源效率，更安静的系统等的社会益处。与地球物理和天体物理流有关的问题也可以以新的，更准确的方式来解决。该教育计划涉及研究生和本科生的参与。拟议的研究的主要目标是通过高雷诺数（RE）渐近级别的综合用途（RE）综合使用和良好分辨的高级实验来开发湍流边界层动力学的多尺度局部微分方程（PDE）模型。从本质上讲，模型开发过程将阐明所谓的“内部/外部”相互作用，因为这些相互作用与边界层的演化有关，因为RE倾向于无穷大。此外，多尺度PDES的数值解有望比原始navier？stokes（ns）方程的直接数值模拟（DNS）较低，从而在其他不可接受的参数方程中启用模拟。提出的模型将与其他最近的努力不同，因为该模型保留了第一原理基础，而不依赖系统输入或现象学假设。该模型基于的多尺度分析将湍流地球物理流的渐近分析，高RE剪切流中的“确切相干结构”以及规范湍流中的平均动力学的最新进展。目标模型是一个封闭的多尺度PDE系统，相对于原始NS方程是自谐和系统地简化的。 只有通过精确的高RE实验才能访问此关键缩放信息。在这方面，大学。新罕布什尔州流动物理设施（FPF）是世界上最大的流动物理质量边界层风隧道，可以在极端雷诺数数字上进行高分辨率测量速度和涡度。