Effective Dissipation and Turbulence in Spectrally Truncated Euler Flows

Cyril Cichowlas (1) , Pauline Bonaïti (1) , Fabrice Debbasch (2) , Marc Brachet (1)

1 LPS - Laboratoire de Physique Statistique de l'ENS
2 LERMA - Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique

A new transient regime in the relaxation towards absolute equilibrium of the conservative and time-reversible 3D Euler equation with a high-wave-number spectral truncation is characterized. Large-scale dissipative effects, caused by the thermalized modes that spontaneously appear between a transition wave number and the maximum wave number, 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 obeys (at least approximately) Kolmogorov scaling.

Domaines: Astrophysique [astro-ph]

Cyril Cichowlas, Pauline Bonaïti, Fabrice Debbasch, Marc Brachet. Effective Dissipation and Turbulence in Spectrally Truncated Euler Flows. Physical Review Letters, 2005, 95, pp.264502. ⟨10.1103/PhysRevLett.95.264502⟩. ⟨hal-03786565⟩