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

摘要信息技术研究（ITR）媒介提案提案号：cts -0324898首席研究员：Ivan Marusic， Victoria Interrante， and Ellen longmir大学/机构：明尼苏达大学ITR：识别、可视化和跟踪实验湍流中涡流演变的动态方法本研究项目将数据可视化和实验流体力学专家结合起来，调查和理解湍流中关键物理机制的动态演变。为了实现这一目标，将研究涡流或涡流结构的演化性质，它们是有壁湍流的基本组成部分。实验将实时跟踪涡流包，这种结构已被确定为在这些流动中产生表面摩擦阻力的关键机制。双立体- piv系统将沿着水道流动的长度进行穿越，同时实施基于可视化工具的特征识别方案，以产生反馈信号。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、破裂等独特而具有挑战性的问题提供答案。将开发适合新实验数据的多元可视化方法。这些方法将被应用于观察哪些结构存在，以及它们是如何发展和衰变的。由于涡旋包具有多个参数的特征，因此挑战在于如何以一种有意义和有用的方式向湍流实践者呈现可视化。多变量可视化将被优化，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达信息。本研究将提供对中高雷诺数壁面湍流关键物理机制动态演化过程的直接认识。这一新发现将在对湍流边界层流动的基本认识方面取得重大进展，并可能导致新的减阻策略和新的湍流模拟方案。此外，适合复杂湍流的可视化方法将被开发出来，这将证明对更广泛的湍流社区以及其他领域的研究人员有用。这项研究将产生独特的漩涡演变电影，将发展成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也将在夏季参加短期调查。教师们被期望将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.