# Self-organisation and non-linear dynamics in driven magnetohydrodynamic turbulent flows

@article{Dallas2014SelforganisationAN, title={Self-organisation and non-linear dynamics in driven magnetohydrodynamic turbulent flows}, author={Vassilios Dallas and Alexandros Alexakis}, journal={arXiv: Plasma Physics}, year={2014} }

Magnetohydrodynamic turbulent flows driven by random mechanical and electromagnetic external forces of zero helicities are investigated by means of direct numerical simulations. It is shown that despite the absence of helicities in the forcing, the system is attracted to self-organized helical states that exhibit laminar behaviour despite the large value of the Reynolds numbers examined. We demonstrate that the correlation time of the external forces is controlling the time spent on these…

## 14 Citations

### Forcing-dependent dynamics and emergence of helicity in rotating turbulence

- PhysicsJournal of Fluid Mechanics
- 2016

The effects of large-scale mechanical forcing on the dynamics of rotating turbulent flows are studied by means of direct numerical simulations, systematically varying the nature of the mechanical…

### Chaotic behavior of Eulerian magnetohydrodynamic turbulence

- PhysicsPhysics of Plasmas
- 2019

We study the chaotic properties of a turbulent conducting fluid using direct numerical simulation in the Eulerian frame. The maximal Lyapunov exponent is measured for simulations with varying…

### Comparison of forcing functions in magnetohydrodynamics

- Physics
- 2017

Results are presented of direct numerical simulations of incompressible, homogeneous magnetohydrodynamic turbulence without a mean magnetic field, subject to different mechanical forcing functions…

### Tridimensional to bidimensional transition in magnetohydrodynamic turbulence with a guide field and kinetic helicity injection

- Physics
- 2016

We study the transition in dimensionality of a three-dimensional magnetohydrodynamic flow forced only mechanically, when the strength of a magnetic guiding field is gradually increased. We use…

### Helicity Dynamics, Inverse, and Bidirectional Cascades in Fluid and Magnetohydrodynamic Turbulence: A Brief Review

- PhysicsEarth and Space Science
- 2019

We briefly review helicity dynamics, inverse and bidirectional cascades in fluid and magnetohydrodynamic (MHD) turbulence, with an emphasis on the latter. The energy of a turbulent system, an…

### Self-organization and transition to turbulence in isotropic fluid motion driven by negative damping at low wavenumbers

- Physics
- 2014

We observe a symmetry-breaking transition from a turbulent to a self-organized state in direct numerical simulation of the Navier–Stokes equation at very low Reynolds number. In this self-organized…

### Helicity dynamics, inverse and bi-directional cascades in fluid and MHD turbulence: A brief review

- Physics
- 2018

We briefly review helicity dynamics, inverse and bi-directional cascades in fluid and magnetohydrodynamic (MHD) turbulence, with an emphasis on the latter. The energy of a turbulent system, an…

### Low-dimensional models of the transition to turbulence

- Physics
- 2019

The transition to turbulence in shear flows such as pressure driven pipe flow or plane Couette flow presents an interesting theoretical problem: how do we understand the existence of chaos when the…

### On-off intermittency and hard turbulence in the flow of fluid in the magnetic field.

- PhysicsChaos
- 2019

An analysis of experiments in which various modes of mercury flow in a constant external magnetic field were observed provides evidence of the chaotic nature of the observed flow modes despite the relative weakness of high-frequency harmonics in comparison to low-frequency ones.

### Spectral properties of homogeneous magnetohydrodynamic turbulence

- Physics
- 2019

Magnetohydrodynamics (MHD) is the study of how an electrically-conducting fluid interacts with a magnetic field. Many of the constituents of the universe possess a magnetic field and MHD has…

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