Spontaneous suppression of inverse energy cascade in instability-driven 2-D turbulence - Aix-Marseille Université Accéder directement au contenu
Article Dans Une Revue Journal of Fluid Mechanics Année : 2022

Spontaneous suppression of inverse energy cascade in instability-driven 2-D turbulence

Résumé

Instabilities of fluid flows often generate turbulence. Using extensive direct numerical simulations, we study two-dimensional turbulence driven by a wavenumber-localised instability superposed on stochastic forcing, in contrast to previous studies of stateindependent forcing. As the contribution of the instability forcing, measured by a parameter γ, increases, the system undergoes two transitions. For γ below a first threshold, a regular large-scale vortex condensate forms. Above this threshold, shielded vortices (SVs) emerge within the condensate. At a second, larger value of γ, the condensate breaks down, and a gas of weakly interacting vortices with broken symmetry spontaneously emerges, characterised by preponderance of vortices of one sign only and suppressed inverse energy cascade. The latter transition is shown to depend on the damping mechanism. The number density of SVs in the broken symmetry state slowly increases via a random nucleation process. Bistability is observed between the condensate and mixed SV-condensate states. Our findings provide new evidence for a strong dependence of two-dimensional turbulence phenomenology on the forcing.
Fichier principal
Vignette du fichier
2206.12355.pdf (4.94 Mo) Télécharger le fichier
Origine : Fichiers produits par l'(les) auteur(s)

Dates et versions

hal-03938532 , version 1 (23-01-2023)

Identifiants

Citer

Adrian van Kan, Benjamin Favier, Keith Julien, Edgar Knobloch. Spontaneous suppression of inverse energy cascade in instability-driven 2-D turbulence. Journal of Fluid Mechanics, 2022, 952, pp.R4. ⟨10.1017/jfm.2022.935⟩. ⟨hal-03938532⟩
19 Consultations
14 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More