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arXiv · 1512.08837

Distributed chaos and isotropic turbulence

A. Bershadskii
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Abstract

Power spectrum of the distributed chaos can be represented by a weighted superposition of the exponential functions which is converged to a stretched exponential $\propto \exp-(k/k_β)^{β}$. An asymptotic theory has been developed in order to estimate the value of $β$ for the isotropic turbulence. This value has been found to be $β=3/4$. Excellent agreement has been established between this theory and the data of direct numerical simulations not only for the velocity field but also for the passive scalar, energy dissipation rate, and magnetic fields. One can conclude that the isotropic turbulence emerges from the distributed chaos.

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A. Bershadskii. 2016-01-11. Distributed chaos and isotropic turbulence. https://arxiv.org/abs/1512.08837

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