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arXiv · 2008.02367

Capturing Turbulent Dynamics and Statistics in Experiments with Unstable Periodic Orbits

Balachandra Suri·Logan Kageorge·Roman O. Grigoriev·Michael F. Schatz
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Abstract

In laboratory studies and numerical simulations, we observe clear signatures of unstable time-periodic solutions in a moderately turbulent quasi-two-dimensional flow. We validate the dynamical relevance of such solutions by demonstrating that turbulent flows in both experiment and numerics transiently display time-periodic dynamics when they shadow unstable periodic orbits (UPOs). We show that UPOs we computed are also statistically significant, with turbulent flows spending a sizable fraction of the total time near these solutions. As a result, the average rates of energy input and dissipation for the turbulent flow and frequently visited UPOs differ only by a few percent.

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Balachandra Suri, Logan Kageorge, Roman O. Grigoriev, Michael F. Schatz. 2020-08-04. Capturing Turbulent Dynamics and Statistics in Experiments with Unstable Periodic Orbits. https://doi.org/10.1103/physrevlett.125.064501

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