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arXiv · 1002.1838

Non-Gaussian buoyancy statistics in fingering convection

Jost von Hardenberg·Francesco Paparella
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Abstract

We examine the statistics of active scalar fluctuations in high-Rayleigh number fingering convection with high-resolution three-dimensional numerical experiments. The one-point distribution of buoyancy fluctuations is found to present significantly non-Gaussian tails. A modified theory based on an original approach by Yakhot (1989) is used to model the active scalar distributions as a function of the conditional expectation values of scalar dissipation and fluxes in the flow. Simple models for these two quantities highlight the role of blob-like coherent structures for scalar statistics in fingering convection.

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BibTeXRIS

Jost von Hardenberg, Francesco Paparella. 2010-02-09. Non-Gaussian buoyancy statistics in fingering convection. https://doi.org/10.1016/j.physleta.2010.04.051

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