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arXiv · 1105.5160

Dynamic Multiscaling in Two-dimensional Fluid Turbulence

Samriddhi Sankar Ray·Dhrubaditya Mitra·Prasad Perlekar·Rahul Pandit
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Abstract

We obtain, by extensive direct numerical simulations, time-dependent and equal-time structure functions for the vorticity, in both quasi-Lagrangian and Eulerian frames, for the direct-cascade regime in two-dimensional fluid turbulence with air-drag-induced friction. We show that differ- ent ways of extracting time scales from these time-dependent structure functions lead to different dynamic-multiscaling exponents, which are related to equal-time multiscaling exponents by different classes of bridge relations; for a representative value of the friction we verify that, given our error bars, these bridge relations hold.

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Samriddhi Sankar Ray, Dhrubaditya Mitra, Prasad Perlekar, Rahul Pandit. 2012-11-23. Dynamic Multiscaling in Two-dimensional Fluid Turbulence. https://doi.org/10.1103/physrevlett.107.184503

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