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Effective Dissipation and Turbulence in Spectrally Truncated Euler Flows

C. Cichowlas·P. Bonaiti·F. Debbasch·M. Brachet
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Abstract

A new transient regime in the relaxation towards absolute equilibrium of the conservative and time-reversible 3-D Euler equation with high-wavenumber spectral truncation is characterized. Large-scale dissipative effects, caused by the thermalized modes that spontaneously appear between a transition wavenumber and the maximum wavenumber, are calculated using fluctuation dissipation relations. The large-scale dynamics is found to be similar to that of high-Reynolds number Navier-Stokes equations and thus to obey (at least approximately) Kolmogorov scaling.

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C. Cichowlas, P. Bonaiti, F. Debbasch, M. Brachet. 2005-12-17. Effective Dissipation and Turbulence in Spectrally Truncated Euler Flows. https://doi.org/10.1103/physrevlett.95.264502

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