From waves to convection and back again: The phase space of stably stratified turbulence

  title={From waves to convection and back again: The phase space of stably stratified turbulence},
  author={Nicol'as E. Sujovolsky and Pablo D. Mininni},
  journal={Physical Review Fluids},
We show that the phase space of stratified turbulence mainly consists of two slow invariant manifolds with rich physics, embedded on a larger basin with fast evolution. A local invariant manifold in the vicinity of the fluid at equilibrium corresponds to waves, while a global invariant manifold corresponds to the onset of local convection. Using a reduced model derived from the Boussinesq equations, we propose that waves accumulate energy nonlinearly up to a point such that fluid elements… 

Interplay between turbulence and waves: large-scale helical transfer, and small-scale dissipation and mixing in fluid and Hall-MHD turbulence

Novel features of turbulent flows have been analyzed recently, for example: (1) the possibility of an ideal invariant, such as the energy, to be transferred both to the small scales and to the large

Coupling Large Eddies and Waves in Turbulence: Case Study of Magnetic Helicity at the Ion Inertial Scale

In turbulence, for neutral or conducting fluids, a large ratio of scales is excited because of the possible occurrence of inverse cascades to large, global scales together with direct cascades to

Correlation between Buoyancy Flux, Dissipation and Potential Vorticity in Rotating Stratified Turbulence

We study in this paper the correlation between the buoyancy flux, the efficiency of energy dissipation and the linear and nonlinear components of potential vorticity, PV, a point-wise invariant of

Connecting large-scale velocity and temperature bursts with small-scale intermittency in stratified turbulence

Non-Gaussian statistics of large-scale fields are routinely observed in data from atmospheric and oceanic campaigns and global models. Recent direct numerical simulations (DNSs) showed that

Analysis of scale-dependent kinetic and potential energy in sheared, stably stratified turbulence

Abstract Budgets of turbulent kinetic energy (TKE) and turbulent potential energy (TPE) at different scales $\ell$ in sheared, stably stratified turbulence are analysed using a filtering approach.

Turbulence generation by large-scale extreme vertical drafts and the modulation of local energy dissipation in stably stratified geophysical flows

Raffaele Marino, Fabio Feraco, Leonardo Primavera, Alain Pumir, Annick Pouquet, Duane Rosenberg, Pablo D. Mininni. Laboratoire de Mécanique des Fluides et d’Acoustique, CNRS, École Centrale de Lyon,



Vertical drafts and mixing in stratified turbulence: Sharp transition with Froude number

We investigate the large-scale intermittency of vertical velocity and temperature, and the mixing properties of stably stratified turbulent flows using both Lagrangian and Eulerian fields from direct

Turbulence comes in bursts in stably stratified flows.

Data from direct numerical simulations of stratified turbulence on grids of 20483 points display the somewhat paradoxical result of measurably stronger events for more stable flows, not only in the temperature and vertical velocity derivatives as commonplace in turbulence, but also in the amplitude of the fields themselves, contrary to what happens for homogenous isotropic turbulent flows.

Stably stratified turbulence in the presence of large-scale forcing.

Some surprising similarities emerge at large scales: The same ratio between potential and total energy (≈0.1) is spontaneously selected by the flows, and slow modes grow monotonically in both regimes, causing a slow increase of the total energy in time.

Waves and vortices in the inverse cascade regime of stratified turbulence with or without rotation

We study the partition of energy between waves and vortices in stratified turbulence, with or without rotation, for a variety of parameters, focusing on the behaviour of the waves and vortices in the

Dynamics of turbulence strongly influenced by buoyancy

The dynamics of quasi-horizontal motions in a stably stratified fluid have been simulated for Froude numbers of order 1, so that the flows are strongly affected by the stable density stratification,

Structures and dynamics of small scales in decaying magnetohydrodynamic turbulence

The topological and dynamical features of small scales are studied in the context of decaying magnetohydrodynamic turbulent flows using direct numerical simulations. Joint probability density

Single-particle Lagrangian statistics from direct numerical simulations of rotating-stratified turbulence

Geophysical fluid flows are predominantly turbulent and often strongly affected by the Earth's rotation, as well as by stable density stratification. Using direct numerical simulations of forced

Detailed investigation of energy transfers in homogeneous stratified turbulence

This paper investigates some irreversible mechanisms occurring in homogeneous stably stratified turbulent flows. In terms of the eigenmodes of the linear regime, the velocity‐temperature field is

Diffusion in stably stratified turbulence

We examine results of direct numerical simulations (DNS) of homogeneous turbulence in the presence of stable stratification. We focus on the effects of stratification on eddy diffusion, and the

Lagrangian Measurements of Waves and Turbulence in Stratified Flows

Abstract Stratified flows are often a mixture of waves and turbulence. Here, Lagrangian frequency is used to distinguish these two types of motion. A set of 52 Lagrangian float trajectories from