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arXiv · 1901.08310

Self-similar Subgrid-scale Models for Inertial Range Turbulence and Accurate Measurements of Intermittency

Luca Biferale·Fabio Bonaccorso·Michele Buzzicotti·Kartik P. Iyer
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Abstract

A class of spectral subgrid models based on a self-similar and reversible closure is studied with the aim to minimize the impact of subgrid scales on the inertial range of fully developed turbulence. In this manner, we improve the scale extension where anomalous exponents are measured by roughly one order of magnitude, when compared to direct numerical simulations or to other popular subgrid closures at the same resolution. We found a first indication that intermittency for high order moments is not captured by many of the popular phenomenological models developed so far.

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Luca Biferale, Fabio Bonaccorso, Michele Buzzicotti, Kartik P. Iyer. 2019-01-24. Self-similar Subgrid-scale Models for Inertial Range Turbulence and Accurate Measurements of Intermittency. https://doi.org/10.1103/physrevlett.123.014503

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