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The Fourth-Order Correlation Function of a Randomly Advected Passive Scalar

E. Balkovsky·M. Chertkov·I. Kolokolov·V. Lebedev
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Abstract

Advection of a passive scalar $θ$ in $d=2$ by a large-scale velocity field rapidly changing in time is considered. The Gaussian feature of the passive scalar statistics in the convective interval was discovered in \cite{95CFKLa}. Here we examine deviations from the Gaussianity: we obtain analytically the simultaneous fourth-order correlation function of $θ$. Explicit expressions for fourth-order objects, like $\langle(θ_1-θ_2)^4\rangle$ are derived.

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E. Balkovsky, M. Chertkov, I. Kolokolov, V. Lebedev. 1995-08-04. The Fourth-Order Correlation Function of a Randomly Advected Passive Scalar. https://arxiv.org/abs/chao-dyn/9508002

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