English
Related papers

Related papers: A numerical study of the alpha model for two-dimen…

200 papers

The effect of a uniform spanwise magnetic field on a turbulent channel flow is investigated for the case of low magnetic Reynolds number. DNS and LES computations are performed for two values of the hydrodynamic Reynolds number (10^4 and…

Fluid Dynamics · Physics 2008-10-14 Dmitry Krasnov , Oleg Zikanov , Joerg Schumacher , Thomas Boeck

We study one-point statistics of spiral turbulent pulsations on the background of three-dimensional large-scale vortex in a rotating fluid. Assuming that the helical flow is created by a statistically axially symmetric random force with…

Fluid Dynamics · Physics 2023-10-31 Leon L. Ogorodnikov , Sergey S. Vergeles

Magnetohydrodynamic turbulence is a ubiquitous phenomenon in solar physics, plasma physics and astrophysics and governs many properties of the flows of well-conductive fluids. Recently, conflicting spectral slopes for the inertial range of…

Astrophysics of Galaxies · Physics 2015-06-18 Andrey Beresnyak

Shallow flows are common in natural and human-made environments. Even for simple rectangular shallow reservoirs, recent laboratory experiments show that the developing flow fields are particularly complex, involving large-scale turbulent…

Fluid Dynamics · Physics 2023-07-13 Daniel Valero , Daniel B. Bung , Sebastien Erpicum , Yann Peltier , Benjamin Dewals

The behavior of the second-order Lagrangian structure functions on state-of-the-art numerical data both in two and three dimensions is studied. On the basis of a phenomenological connection between Eulerian space-fluctuations and the…

Fluid Dynamics · Physics 2014-03-13 Alessandra S. Lanotte , Luca Biferale , Guido Boffetta , Federico Toschi

Lagrangian properties obtained from a Particle Tracking Velocimetry experiment in a turbulent flow at intermediate Reynolds number are presented. Accurate sampling of particle trajectories is essential in order to obtain the Lagrangian…

Fluid Dynamics · Physics 2015-05-13 Jacob Berg , Soren Ott , Jakob Mann , Beat Luthi

Astrophysical turbulence is magnetohydrodynamic (MHD) in its nature. We discuss fundamental properties of MHD turbulence. In particular, we discuss the generation of compressible MHD waves by Alfvenic turbulence and show that this process…

Astrophysics · Physics 2016-08-30 Jungyeon Cho , A. Lazarian

Weak turbulence of magnetohydrodynamic (MHD) waves in strongly magnetized plasma is studied when the thermal pressure is less than the magnetic field pressure. In this situation the main nonlinear mechanism is the resonance scattering of…

Plasma Physics · Physics 2009-11-07 Evgenii A. Kuznetsov

We compare the properties of ordinary strong magnetohydrodynamic (MHD) turbulence in a strongly magnetized medium with the recently discovered viscosity-damped regime. We focus on energy spectra, anisotropy, and intermittency. Our most…

Astrophysics · Physics 2009-11-07 Jungyeon Cho , A. Lazarian , Ethan T. Vishniac

The Magneto-hydrodynamic (MHD) equations in the presence of a guiding magnetic field are investigated by means of direct numerical simulations. The basis of the investigation consists of 9 runs forced at the small scales. The results…

Fluid Dynamics · Physics 2015-05-30 Alexandros Alexakis

In this paper, we propose, analyze, and test an efficient algorithm for computing ensemble average of incompressible magnetohydrodynamics (MHD) flows, where instances/members correspond to varying kinematic viscosity, magnetic diffusivity,…

Numerical Analysis · Mathematics 2021-08-12 Muhammad Mohebujjaman , Hongwei Wang , Leo G. Rebholz , Md. Abdullah Al Mahbub

An analytical model for three-dimensional incompressible turbulence was recently introduced in the hydrodynamics community which, with only a few parameters, shares many properties of experimental and numerical turbulence, notably…

Astrophysics of Galaxies · Physics 2021-01-13 J. -B. Durrive , K. Ferrière , P. Lesaffre

Intermittency is an essential property of astrophysical fluids, which demonstrate an extended inertial range. As intermittency violates self-similarity of motions, it gets impossible to naively extrapolate the properties of fluid obtained…

Astrophysics · Physics 2011-05-10 A. Lazarian

A new simulation set-up is proposed for studying mean field dynamo action. The model combines the computational advantages of local cartesian geometry with the ability to include a shear profile that resembles the sun's differential…

Astrophysics · Physics 2007-05-23 Axel Brandenburg , Christer Sandin

We use the multifractal formalism to describe the effects of dissipation on Lagrangian velocity statistics in turbulent flows. We analyze high Reynolds number experiments and direct numerical simulation (DNS) data. We show that this…

Statistical Mechanics · Physics 2007-05-23 L. Chevillard , S. G. Roux , E. Leveque , N. Mordant , J. -F. Pinton , A. Arneodo

Observations show that transverse magnetohydrodynamic (MHD) waves and flows are often simultaneously present in magnetic loops of the solar corona. The waves are resonantly damped in the Alfv\'en continuum because of plasma and/or magnetic…

Solar and Stellar Astrophysics · Physics 2019-03-06 Roberto Soler

We explore the suitability of deep learning to capture the physics of subgrid-scale ideal magnetohydrodynamics turbulence of 2-D simulations of the magnetized Kelvin-Helmholtz instability. We produce simulations at different resolutions to…

Computational Physics · Physics 2020-08-27 Shawn G. Rosofsky , E. A. Huerta

Herein, we derive the fractional Laplacian operator as a means to represent the mean friction force arising in a turbulent flow: $ \rho \frac{D\bar{\bf u}}{Dt} = -\nabla p + \mu_\alpha \nabla^2\bar{\bf u} + \rho C_\alpha…

Fluid Dynamics · Physics 2018-03-15 Brenden P. Epps , Benoit Cushman-Roisin

Turbulence is the most common state of astrophysical flows. In typical astrophysical fluids, turbulence is accompanied by strong magnetic fields, which has a large impact on the dynamics of the turbulent cascade. Recently, there has been a…

Astrophysics · Physics 2007-05-23 A. Lazarian , Jungyeon Cho , Huirong Yan

Single fluid magnetohydrodynamic (MHD) equations have been studied through direct numerical simulations (DNS) using pseudo-spectral methods in two as well as three spatial dimensions. At Alfv\'en resonance, a reversible periodic exchange of…

Plasma Physics · Physics 2019-06-24 Rupak Mukherjee , Rajaraman Ganesh , Abhijit Sen