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Universality of anisotropic fluctuations from numerical simulations of turbulent flows

L. Biferale·E. Calzavarini·F. Toschi·R. Tripiccione
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Abstract

We present new results from a direct numerical simulation of a three dimensional homogeneous Rayleigh-Benard system (HRB), i.e. a convective cell with an imposed linear mean temperature profile along the vertical direction. We measure the SO(3)-decomposition of both velocity structure functions and buoyancy terms. We give a dimensional prediction for the values of the anisotropic scaling exponents in this Rayleigh-Benard systems. Measured scaling does not follow dimensional estimate, while a better agreement can be found with the anisotropic scaling of a different system, the random-Kolmogorov-flow (RKF). Our findings support the conclusion that scaling properties of anisotropic fluctuations are universal, i.e. independent of the forcing mechanism sustaining the turbulent flow.

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L. Biferale, E. Calzavarini, F. Toschi, R. Tripiccione. 2003-02-14. Universality of anisotropic fluctuations from numerical simulations of turbulent flows. https://doi.org/10.1209/epl%2Fi2003-00233-9

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