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The large-scale structure of passive scalar turbulence

Antonio Celani·Agnese Seminara
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Abstract

We investigate the large-scale statistics of a passive scalar transported by a turbulent velocity field. At scales larger than the characteristic lengthscale of scalar injection, yet smaller than the correlation length of the velocity, the advected field displays persistent long-range correlations due to the underlying turbulent velocity. These induce significant deviations from equilibrium statistics for high-order scalar correlations, despite the absence of scalar flux.

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Antonio Celani, Agnese Seminara. 2005-01-03. The large-scale structure of passive scalar turbulence. https://doi.org/10.1103/physrevlett.94.214503

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