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arXiv · 1302.6693

What a single snapshot reveals about the future and the past of turbulent flow

Gregory Falkovich·Anna Frishman
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Abstract

We develop an analytic formalism and derive new exact relations that express the short-time dispersion of fluid particles via the single-time velocity correlation functions in homogeneous isotropic and incompressible turbulence. The formalism establishes a bridge between single-time Eulerian and long-time Lagrangian pictures of turbulent flows. In particular, we derive an exact formula for a short-term analog of the long-time Richardson law, and we identify a conservation law of turbulent dispersion which is true even in non-stationary turbulence.

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Gregory Falkovich, Anna Frishman. 2013-02-27. What a single snapshot reveals about the future and the past of turbulent flow. https://doi.org/10.1103/physrevlett.110.214502

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