ITR: Dynamic Methods for Identifying, Visualizing, and Tracking Eddy Evolution in Experimental Turbulent Flows

信息技术研究(ITR)中等建议编号：CTS-0324898主要研究人员：Ivan Marusic、Victoria Interrante和Ellen LongmireUniversity/研究所：明尼苏达大学ITR：识别、可视化和跟踪实验湍流中的涡旋演化的动态方法本研究计划联合数据可视化和实验流体力学专家来研究和理解湍流中关键物理机制的动态演变。为了实现这一点，我们将研究旋涡或旋涡结构的演变性质，这些旋涡是壁面湍流中的基本构件。实验将实时跟踪涡包，这是已被确定为在这些流动中产生表面摩擦阻力的关键机制的结构。在实施基于可视化工具的特征识别方案以产生反馈信号的同时，将沿着水通道流的长度遍历双立体声PIV系统。实验和特征检测策略将为壁面湍流中涡包结构和其他主要流动特征的产生、发展、合并和相互作用、破坏和破坏等独特而具有挑战性的问题提供答案。将开发适合于新实验数据的多变量可视化方法。这些方法将被应用于观察存在什么结构，以及它们是如何发展和衰败的。由于涡旋包具有多个参数的特征，因此挑战在于以一种有意义且有用的方式向湍流实践者呈现可视化。多变量可视化将得到优化，特别注意量化不同的视觉特征，如颜色、纹理、地形和运动，如何以及为什么有效地传递信息。这一研究将直接揭示中、高雷诺数下壁面湍流中关键物理机制的动态演化过程。这一新的洞察力将构成对湍流边界层流动基本认识的重大进步，并可能导致新的减阻策略和新的湍流模拟方案。此外，还将开发适合于复杂湍流的可视化方法，这些方法将被证明对更广泛的湍流社区以及其他领域的研究人员有用。这项研究将导致独特的漩涡进化电影，将被开发为研究生课程和更广泛的科学观众的教育资源。除了研究生，本科生和高中物理教师还将在暑期参加短期调查。预计教师将把他们在尖端测量技术和工程应用方面的经验带回课堂。

AbstractInformation Technology Research (ITR) Medium ProposalsProposal Number: CTS-0324898Principal Investigator: Ivan Marusic, Victoria Interrante, and Ellen LongmireUniversity/Institution: University of MinnesotaITR: Dynamic methods for Identifying, Visualizing and Tracking Eddy Evolution in Experimental Turbulent FlowsThis research program unites data visualization and experimental fluid mechanics specialists to investigate and understand the dynamic evolution of key physical mechanisms in turbulent flows. To accomplish this, the evolving nature of eddies, or vortex structures, fundamental building blocks in wall-bounded turbulent flows, will be examined. Experiments will track, in real time, vortex packets, which are structures that have been identified as a key mechanism in producing skin-friction drag in these flows. A dual stereo-PIV system will be traversed along the length of a water channel flow while implementing a feature-identification scheme based on visualization tools to generate a feedback signal. The experiments and feature detection strategies will provide answers to unique and challenging questions about the generation, development, merging and interaction, and breakdown of vortex packet structures and other dominant flow features in wall turbulence. Multivariate visualization methods appropriate for the novel experimental data will be developed. The methods will be applied to see what structures exist, and how they develop and decay. Because vortex packets are characterized by several parameters, the challenge is to present the visualization in a meaningful and useful way to turbulence practitioners. The multivariate visualizations will be optimized with special attention paid to quantifying how and why different visual features, such as color, texture, topography, and motion, work to convey information efficiently and effectively. This research will provide, direct insight into the dynamic evolution processes of key physical mechanisms in wall turbulence at moderate to high Reynolds numbers. The new insight will constitute a major advance in the fundamental understanding of turbulent boundary layer flows and can lead to new drag reduction strategies and new turbulence simulation schemes. Also, visualization methods suited to complex turbulent flows will be developed that will prove useful to the broader turbulence community as well in researchers in additional fields. This research will lead to unique movies of vortex evolution that will be developed into an educational resource for graduate programs and broader scientific audiences. In addition to graduate students, undergraduates and high school physics teachers will participate in short-term investigations during the summers. The teachers are expected to bring their experiences with cutting edge measurement techniques and engineering applications back to the classroom.