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Synthetic Turbulence, Fractal Interpolation and Large-Eddy Simulation

Sukanta Basu·Efi Foufoula-Georgiou·Fernando Porté-Agel
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Abstract

Fractal Interpolation has been proposed in the literature as an efficient way to construct closure models for the numerical solution of coarse-grained Navier-Stokes equations. It is based on synthetically generating a scale-invariant subgrid-scale field and analytically evaluating its effects on large resolved scales. In this paper, we propose an extension of previous work by developing a multiaffine fractal interpolation scheme and demonstrate that it preserves not only the fractal dimension but also the higher-order structure functions and the non-Gaussian probability density function of the velocity increments. Extensive a-priori analyses of atmospheric boundary layer measurements further reveal that this Multiaffine closure model has the potential for satisfactory performance in large-eddy simulations. The pertinence of this newly proposed methodology in the case of passive scalars is also discussed.

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BibTeXRIS

Sukanta Basu, Efi Foufoula-Georgiou, Fernando Porté-Agel. 2003-10-27. Synthetic Turbulence, Fractal Interpolation and Large-Eddy Simulation. https://doi.org/10.1103/physreve.70.026310

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