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arXiv · 2204.02357

Ensemble model of turbulence based on states of constant flux in wavenumber space

Kyo Yoshida
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Abstract

An ensemble model of turbulence is proposed. The ensemble consists of flow fields in which the flux of an inviscid conserved quantity, such as energy (or enstrophy in two-dimensional flow fields), across the wavenumber $k$ is a constant independent of $k$ in an appropriate range. Two-dimensional flow fields of constant enstrophy flux are sampled randomly by a Monte Carlo method. The energy spectra $E_k$ of the flow fields are consistent with the scaling $E_k \propto k^{-3}(\ln(k/k_\mathrm{b}))^{-1/3}$ where $k_\mathrm{b}$ is the bottom wavenumber of the constant-flux range.

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Kyo Yoshida. 2022-04-05. Ensemble model of turbulence based on states of constant flux in wavenumber space. https://doi.org/10.1103/physreve.106.045106

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