Self-similar regimes of turbulence in weakly coupled plasmas under compression - Archive ouverte HAL Access content directly
Journal Articles Physical Review E Year : 2018

Self-similar regimes of turbulence in weakly coupled plasmas under compression

Abstract

Turbulence in weakly coupled plasmas under compression can experience a sudden dissipation of kinetic energy due to the abrupt growth of the viscosity coefficient governed by the temperature increase. We investigate in detail this phenomenon by considering a turbulent velocity field obeying the incompressible Navier-Stokes equations with a source term resulting from the mean velocity. The system can be simplified by a nonlinear change of variable, and then solved using both highly resolved direct numerical simulations and a spectral model based on the eddy-damped quasinormal Markovian closure. The model allows us to explore a wide range of initial Reynolds and compression numbers, beyond the reach of simulations, and thus permits us to evidence the presence of a nonlinear cascade phase. We find self-similarity of intermediate regimes as well as of the final decay of turbulence, and we demonstrate the importance of initial distribution of energy at large scales. This effect can explain the global sensitivity of the flow dynamics to initial conditions, which we also illustrate with simulations of compressed homogeneous isotropic turbulence and of imploding spherical turbulent layers relevant to inertial confinement fusion.
Fichier principal
Vignette du fichier
PhysRevE.97.023201.pdf (1.88 Mo) Télécharger le fichier
Origin : Publisher files allowed on an open archive
Loading...

Dates and versions

hal-02084835 , version 1 (21-02-2020)

Identifiers

Cite

Giovanni Viciconte, Benoît-Joseph Gréa, Fabien S. Godeferd. Self-similar regimes of turbulence in weakly coupled plasmas under compression. Physical Review E , 2018, 97, pp.023201. ⟨10.1103/PhysRevE.97.023201⟩. ⟨hal-02084835⟩
120 View
106 Download

Altmetric

Share

Gmail Facebook X LinkedIn More