Information Technology Research (ITR) Medium Proposals
Proposal Number: CTS-0324898 Principal Investigator: Ivan Marusic, Victoria Interrante, and Ellen Longmire University/Institution: University of Minnesota
ITR: Dynamic methods for Identifying, Visualizing and Tracking Eddy Evolution in Experimental Turbulent Flows This 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.
