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Universality of Velocity Gradients in Forced Burgers Turbulence

Jeremie Bec
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Abstract

It is demonstrated that Burgers turbulence subject to large-scale white-noise-in-time random forcing has a universal power-law tail with exponent -7/2 in the probability density function of negative velocity gradients, as predicted by E, Khanin, Mazel and Sinai (1997, Phys. Rev. Lett. 78, 1904). A particle and shock tracking numerical method gives about five decades of scaling. Using a Lagrangian approach, the -7/2 law is related to the shape of the unstable manifold associated to the global minimizer.

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Jeremie Bec. 2001-10-24. Universality of Velocity Gradients in Forced Burgers Turbulence. https://doi.org/10.1103/physrevlett.87.104501

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