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A model differential equation for turbulence

Colm Connaughton·Sergey Nazarenko
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Abstract

A phenomenological turbulence model in which the energy spectrum obeys a nonlinear diffusion equation is presented. This equation respects the scaling properties of the original Navier-Stokes equations and it has the Kolmogorov -5/3 cascade and the thermodynamic equilibrium spectra as exact steady state solutions. The general steady state in this model contains a nonlinear mixture of the constant-flux and thermodynamic components. Such "warm cascade" solutions describe the bottleneck phenomenon of spectrum stagnation near the dissipative scale. Self-similar solutions describing a finite-time formation of steady cascades are analysed and found to exhibit nontrivial scaling behaviour.

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Colm Connaughton, Sergey Nazarenko. 2003-04-22. A model differential equation for turbulence. https://arxiv.org/abs/physics/0304044

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