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Related papers: Kazantsev dynamo in turbulent compressible flows

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The solar wind is a magnetized and turbulent plasma. Its turbulence is often dominated by Alfv\'enic fluctuations and often deemed as nearly incompressible far away from the Sun, as shown by in-situ measurements near 1AU. However, for solar…

Solar and Stellar Astrophysics · Physics 2022-09-14 Xiangrong Fu , Hui Li , Zhaoming Gan , Senbei Du , John Steinberg

For a freely evolving granular fluid, the buildup of spatial correlations in density and flow field is described using fluctuating hydrodynamics. The theory for incompressible flows is extended to the general, compressible case, including…

Statistical Mechanics · Physics 2009-10-30 T. P. C. van Noije , M. H. Ernst , R. Brito

Transport of scalar fields in compressible flow is investigated. The effective equations governing the transport at scales large compared to those of the advecting flow are derived by using multi-scale techniques. Ballistic transport…

chao-dyn · Physics 2009-10-28 M. Vergassola , M. Avellaneda

Kinematic dynamo theory is presented here for turbulent conductive fluids. We describe how inhomogeneous magnetic fluctuations are generated below the viscous scale of turbulence where the spatial smoothness of the velocity permits a…

chao-dyn · Physics 2009-10-31 M. Chertkov , G. Falkovich , I. Kolokolov , M. Vergassola

We consider the kinematic stage of evolution of magnetic field advected by turbulent hydrodynamic flow. We use a generalization of the Kazantsev-Kraichnan model to investigate time irreversible flows. In the viscous range of scales, the…

Fluid Dynamics · Physics 2023-10-26 A. V. Kopyev , A. S. Il'yn , V. A. Sirota , K. P. Zybin

We study the dynamo instability driven by a turbulent two dimensional flow with three components of the form (u(x, y, t), v(x, y, t), w(x, y, t)) sometimes referred to as a 2.5 dimensional flow. This type of flows provides an approximation…

Fluid Dynamics · Physics 2016-08-24 K. Seshasayanan , A. Alexakis

We study the growth of small fluctuations of magnetic field in supersonic turbulence, the small-scale dynamo. The growth is due to the fastest turbulent eddies above the resistive scale. We observe that for supersonic turbulence these…

Fluid Dynamics · Physics 2020-03-11 Itzhak Fouxon , Michael Mond

We study dynamo action in a convective layer of electrically-conducting, compressible fluid, rotating about the vertical axis. At the upper and lower bounding surfaces, perfectly-conducting boundary conditions are adopted for the magnetic…

Solar and Stellar Astrophysics · Physics 2011-11-23 Benjamin F. N. Favier , Paul J. Bushby

The small-scale turbulent dynamo in the high Prandtl number regime is described in terms of the one-point Fourier space correlators. The second order correlator of this kind is the energy spectrum and it has been previously studied in…

Astrophysics · Physics 2009-11-07 S. Nazarenko , R. J. West , O. Zaboronski

Turbulent flows are strongly chaotic and unpredictable, with a Lyapunov exponent that increases with the Reynolds number. Here, we study the chaoticity of the Surface Quasi-geostrophic system, a two-dimensional model for geophysical flows…

Fluid Dynamics · Physics 2025-07-28 V. J. Valadão , F. De Lillo , S. Musacchio , G. Boffetta

A key feature of turbulent suspensions that involve floating particles on the surface or inertial particles in the bulk is the compressibility of the effective particle-phase velocity field. Little, however, is known about the effects of…

Fluid Dynamics · Physics 2025-12-10 Dipankar Roy , Marco Martins Afonso , Jason R. Picardo , Dario Vincenzi

We establish exact inequalities for the structure-function scaling exponents of a passively advected scalar in both the inertial-convective and viscous-convective ranges. These inequalities involve the scaling exponents of the velocity…

chao-dyn · Physics 2009-10-28 Gregory L. Eyink

The emergence upon cooling of an ordered solid phase from a liquid is a remarkable example of self-assembly, which has also major practical relevance. Here, we use a recently developed committor-based enhanced sampling method [Kang et al.,…

Statistical Mechanics · Physics 2025-06-30 Yuanpeng Deng , Peilin Kang , Xiang Xu , Hui Li , Michele Parrinello

We consider kinematic dynamo action in rapidly rotating Boussinesq convection just above onset. The velocity is constrained to have either a square or a hexagonal pattern. For the square pattern, large-scale dynamo action is observed at…

Fluid Dynamics · Physics 2015-06-17 B. Favier , M. R. E. Proctor

The linearized Navier-Stokes equations for a system of superposed immiscible compressible ideal fluids are analyzed. The results of the analysis reconcile the stabilizing and destabilizing effects of compressibility reported in the…

Fluid Dynamics · Physics 2009-11-10 Daniel Livescu

We propose an exact analytical formula for the anomalous scaling exponents of inertial range structure functions in incompressible fluid turbulence. The formula is a gravitational Knizhnik-Polyakov-Zamolodchikov (KPZ)-type relation, and is…

Chaotic Dynamics · Physics 2015-10-28 Christopher Eling , Yaron Oz

Consider a linear elliptic partial differential equation in divergence form with a random coefficient field. The solution operator displays fluctuations around its expectation. The recently developed pathwise theory of fluctuations in…

Analysis of PDEs · Mathematics 2021-12-01 Mitia Duerinckx , Julian Fischer , Antoine Gloria

The thermodynamics of excited nuclear systems allows one to explore the second-order phase transition in a two-component quantum mixture. Temperatures and densities are derived from quantum fluctuations of fermions. The pressures are…

The turbulent dynamo may explain the origin of cosmic magnetism. While the exponential amplification of magnetic fields has been studied for incompressible gases, little is known about dynamo action in highly-compressible, supersonic…

Astrophysics of Galaxies · Physics 2014-12-05 Christoph Federrath , Jennifer Schober , Stefano Bovino , Dominik R. G. Schleicher

We consider an advection of a passive scalar by a flow which is a superposition of random waves. We find that such a flow can lead to an exponential growth of the passive scalar fluctuations. We calculate the growth rate at the fourth order…

Chaotic Dynamics · Physics 2007-05-23 A. M. Balk. G. Falkovich , M. S. Stepanov