Large time behavior and asymptotic stability of the 2D Euler and linearized Euler equations

PHYSICA D-NONLINEAR PHENOMENA

卷:239

Article

Bouchet, Freddy^1,2  Morita, Hidetoshi¹ 

[1] UNSA, CNRS, INLN, F-06560 Valbonne, France

[2] Los Alamos Natl Lab, CNLS, Los Alamos, NM 87545 USA

关键词: 2D Euler equations;    Large scales of turbulent flows;    2D turbulence;    Geophysical turbulence;    Asymptotic behavior;    Asymptotic stability;   

DOI  :  10.1016/j.physd.2010.01.020

来源: Elsevier

【 摘 要 】

We study the asymptotic behavior and the asymptotic stability of the 2D Euler equations and of the 2D linearized Euler equations close to parallel flows. We focus on flows with spectrally stable profiles U (y) and with stationary streamlines y = y(0) (such that U'(y(0)) = 0), a case that has not been studied previously. We describe a new dynamical phenomenon: the depletion of the vorticity at the stationary streamlines. An unexpected consequence is that the velocity decays for large times with power laws, similarly to what happens in the case of the Orr mechanism for base flows without stationary streamlines. The asymptotic behaviors of velocity and the asymptotic profiles of vorticity are theoretically predicted and compared with direct numerical simulations. We argue on the asymptotic stability of this ensemble of flow profiles even in the absence of any dissipative mechanisms. (c) 2010 Elsevier B.V. All rights reserved.

【 授权许可】

Free