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Related papers: Influence of turbulence on the dynamo threshold

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We investigate the saturation level of hydromagnetic turbulence driven by the magnetorotational instability in the case of vanishing net flux. Motivated by a recent paper of Bodo, Cattaneo, Mignone, & Rossi, we here focus on the case of a…

High Energy Astrophysical Phenomena · Physics 2015-06-15 Oliver Gressel

The random intensity of noise approach to 1D Laval-Dubrulle-Nazarenko model is used to describe Lagrangian acceleration of a fluid particle in developed turbulence. Intensities of noises entering nonlinear Langevin equation are assumed to…

Statistical Mechanics · Physics 2007-05-23 A. K. Aringazin , M. I. Mazhitov

This paper presents an analysis of the effects of noise and precision on a simplified model of the clarinet driven by a variable control parameter. When the control parameter is varied the clarinet model undergoes a dynamic bifurcation. A…

Classical Physics · Physics 2013-11-21 Baptiste Bergeot , André Almeida , Christophe Vergez , Bruno Gazengel

It has previously been shown that by increasing the Reynolds number across a channel by spatially varying the viscosity does not cause an immediate change in the size of turbulent structures and a delay is in fact observed in both wall…

Fluid Dynamics · Physics 2021-06-11 Victor Coppo Leite , Elia Merzari

In an attempt to determine the outer scale of turbulence driven by localized sources, such as supernova explosions in the interstellar medium, we consider a forcing function given by the gradient of gaussian profiles localized at random…

Astrophysics · Physics 2007-05-23 Antony J. Mee , Axel Brandenburg

Planetary and stellar dynamos likely result from turbulent motions in magnetofluids with kinematic viscosities that are small compared to their magnetic diffusivities. Laboratory experiments are in progress to produce similar dynamos in…

Astrophysics · Physics 2009-11-11 P. D. Mininni

In this work we analyze the stochastic dynamics of the Kauffman model evolving under the influence of noise. By considering the average crossing time between two distinct trajectories, we show that different Kauffman models exhibit a…

Adaptation and Self-Organizing Systems · Physics 2015-06-26 X. Qu , M. Aldana , Leo P. Kadanoff

The influence of turbulent effects on a fluid flow through a (pseudo) porous media is studied by numerically solving the set of Reynolds-averaged Navier-Stokes equations with the $\kappa$-$\epsilon$ model for turbulence. The spatial domains…

Statistical Mechanics · Physics 2009-11-07 H. H. M. Vasconcelos , U. M. S. Costa , M. P. Almeida

The turbulent magnetic diffusivity tensor is determined in the presence of rotation or shear. The question is addressed whether dynamo action from the shear-current effect can explain large-scale magnetic field generation found in…

Astrophysics · Physics 2010-11-05 A. Brandenburg , K. -H. Rädler , M. Rheinhardt , P. J. Käpylä

We study the appearance of large scale mean motion sustained by stochastic forcing on a rotating fluid (in the quasigeostrophic approximation) flowing over topography. As in other noise rectification phenomena, the effect requires…

chao-dyn · Physics 2009-10-31 Alberto Alvarez , Emilio Hernandez-Garcia , Joaquin Tintore

The creation and subsequent evolution of marginally-unstable modes have been observed in a wide range of fusion devices. This behaviour has been successfully explained, for a single frequency shifting mode, in terms of phase-space…

Using the test-field method for nearly irrotational turbulence driven by spherical expansion waves it is shown that the turbulent magnetic diffusivity increases with magnetic Reynolds numbers. Its value levels off at several times the rms…

Astrophysics of Galaxies · Physics 2010-11-05 Axel Brandenburg , Fabio Del Sordo

We study the effect of turbulence on collisions between a finite-size bubble and small inertial particles based on interface-resolved simulations. Our results show that the interaction with the flow field around the bubble remains the…

Fluid Dynamics · Physics 2025-01-14 Linfeng Jiang , Dominik Krug

We study the phenomenon of turbulence initiation in pipe flow under different noise structures by estimating the probability of initiating metastable transitions. We establish lower bounds on turbulence transition probabilities using…

Probability · Mathematics 2025-03-04 Paolo Bernuzzi , Christian Kuehn

The impact of intrinsic compressibility effects -- changes in fluid volume due to pressure variations -- on high-speed wall-bounded turbulence has often been overlooked or incorrectly attributed to mean property variations. To unambiguously…

Fluid Dynamics · Physics 2025-03-19 Asif Manzoor Hasan , Pedro Costa , Johan Larsson , Sergio Pirozzoli , Rene Pecnik

Predicting particle-laden flows requires accurate fluid force models. However, a reliable particle force model for finite-size particles in turbulent flows remains lacking. In the present work, a fluid force model for a finite-size…

Fluid Dynamics · Physics 2025-05-29 Yuqi Wang , Ruifeng Hu

To understand the basic mechanism of the formation of magnetic flux concentrations, we determine by direct numerical simulations the turbulence contributions to the mean magnetic pressure in a strongly stratified isothermal layer with large…

Solar and Stellar Astrophysics · Physics 2015-03-17 Axel Brandenburg , Koen Kemel , Nathan Kleeorin , Igor Rogachevskii

We study the effects of crosscorrelations of noises on the scaling properties of the correlation functions in a reduced model for Magnetohydrodynamic (MHD) turbulence [A. Basu, J.K Bhattacharjee and S. Ramaswamy [{\em Eur. Phys. J B} {\bf…

Chaotic Dynamics · Physics 2007-05-23 Abhik Basu

We study the homogeneous isotropic turbulence of a shear-thinning fluid modeled by the Carreau model and show how the variable viscosity affects the multiscale behaviour of the turbulent flow. We show that Kolmogorov theory can be extended…

Fluid Dynamics · Physics 2025-06-11 Marco Edoardo Rosti

We add thermal noise consistently to reduced models of undeformable vesicles and capsules in shear flow and derive analytically the corresponding stochastic equations of motion. We calculate the steady-state probability distribution…

Soft Condensed Matter · Physics 2012-07-31 David Abreu , Udo Seifert