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Related papers: Low inertia reversing geodynamos

200 papers

Convective flow in Earth's iron-rich liquid core drives self-sustained dynamo action, generating Earth's magnetic field, which is strongest among all terrestrial planets of the solar system. Rock records show that this magnetic field has…

Earth and Planetary Astrophysics · Physics 2025-08-04 Urmi Dutta , Chris J. Davies , Ashley P. Willis

Polarity reversals are a key feature of Earth's magnetic field, yet the processes governing them are still poorly understood. Dipole reversals have been found in many numerical dynamo simulations and often occur close to the transition…

Geophysics · Physics 2025-05-13 Andrew T. Clarke , Christopher J. Davies , Souvik Naskar , Stephen J. Mason

The problem of the turbulent thermal convection in the Earth's liquid core is considered. Following assumptions on decreasing of the spatial scales due to the rapid rotation, we propose the subgrid model of the eddy diffusivity, which is…

Fluid Dynamics · Physics 2007-05-23 M. Reshetnyak , B. Steffen

This paper provides a brief overview of dynamo scaling relationships for the degree of equipartition between magnetic and kinetic energies. Three basic approaches are adopted to explore these scaling relationships, with a first look at two…

Solar and Stellar Astrophysics · Physics 2017-01-11 Kyle Augustson , Stéphane Mathis , Allan Sacha Brun

In this work 2D Ising systems were used to simulate the reversals of the Earth's magnetic field. Each spin was supposed to be a ring current in the Earth dynamo and the magnetization to be proportional to the field intensity. Given the…

Geophysics · Physics 2007-05-23 Jorge O. O. Franco , Vitor H. A. Dias , Andres R. R. Papa

Earlier, Chicone, Latushkin and Montgomery-Smith [Comm Math Phys (1997)] have proved the existence of a fast dynamo operator, in compact two-dimensional manifold, as long as its Riemannian curvature be constant and negative. More recently…

Mathematical Physics · Physics 2009-11-03 L Garcia de Andrade

Flow reversals are rarely observed in low-Prandtl-number liquid metal convection due to the fluid's exceptionally high thermal diffusivity. Here, we demonstrate that an external transverse magnetic field can induce such reversals in a…

Fluid Dynamics · Physics 2025-11-11 Yan-Wu Cao , Ming-Zhu Ai , Long Chen , Juan-Cheng Yang , Ming-Jiu Ni

We solve the equations of motion of a one-dimensional planar Heisenberg (or Vaks-Larkin) model consisting of a system of interacting macro-spins aligned along a ring. Each spin has unit length and is described by its angle with respect to…

Earth and Planetary Astrophysics · Physics 2015-03-19 N. Mori , D. Schmitt , A. Ferriz-Mas , J. Wicht , H. Mouri , A. Nakamichi , M. Morikawa

The surface layers of the Sun are strongly stratified. In the presence of turbulence with a weak mean magnetic field, a large-scale instability resulting in the formation of non-uniform magnetic structures, can be excited over the scale of…

Solar and Stellar Astrophysics · Physics 2015-12-16 Illa R. Losada , A. Brandenburg , N. Kleeorin , Dhrubaditya Mitra , I. Rogachevskii

Amplification of magnetic field due to kinematic turbulent dynamo action is studied in the regime of small magnetic Prandtl numbers. Such a regime is relevant for planets and stars interiors, as well as for liquid metal laboratory…

Solar and Stellar Astrophysics · Physics 2015-05-20 Leonid M. Malyshkin , Stanislav Boldyrev

We investigate small-scale dynamo action in the solar convection zone through a series of high resolution MHD simulations in a local Cartesian domain with 1$R_\odot$ (solar radius) of horizontal extent and a radial extent from 0.715 to…

Solar and Stellar Astrophysics · Physics 2015-06-23 H. Hotta , M. Rempel , T. Yokoyama

State of the art numerical models of the Geodynamo are still performed in a parameter regime extremely remote from the values relevant to the physics of the Earth's core. In order to establish a connection between dynamo modeling and the…

Geophysics · Physics 2015-06-18 Ludivine Oruba , Emmanuel Dormy

Spectropolarimetric observations show that many low-mass stars possess large-scale poloidal magnetic fields with considerable dipole component, which in some cases exhibit temporal dynamics - cycles or reversals. Although it is widely…

Solar and Stellar Astrophysics · Physics 2025-07-02 Anna Guseva , Ludovic Petitdemange , Charly Pinçon

The dynamics of convecting fluids in rotating spherical shells is governed at Prandtl numbers of the order unity by the interaction between differential rotation and roll-like convection eddies. While the differential rotation is driven by…

Fluid Dynamics · Physics 2009-05-25 F. H. Busse , R. D. Simitev

Numerical experiments of dynamo action designed to understand the generation of Earth's magnetic field produce different regime branches identified within bifurcation diagrams. Notable are distinct branches where the resultant magnetic…

Geophysics · Physics 2025-08-11 Robert J. Teed , Emmanuel Dormy

We use the ASH code to model the convective dynamo of solar-type stars. Based on a series of 15 3-D MHD simulations spanning 4 bins in rotation and mass, we show what mechanisms are at work in these stellar dynamos with and without magnetic…

Solar and Stellar Astrophysics · Physics 2022-02-16 Allan Sacha Brun , Antoine Strugarek , Quentin Noraz , Barbara Perri , Jacobo Varela , Kyle Augsutson , Paul Charbonneau , Juri Toomre

We study a simple magnetohydrodynamical approach in which hydrodynamics and MHD turbulence are coupled in a shell model, with given dynamo constrains in the large scales. We consider the case of a low Prandtl number fluid for which the…

Earth and Planetary Astrophysics · Physics 2015-05-13 Roberto Benzi , Jean-Francois Pinton

We study the onset of magnetoconvection between two infinite horizontal planes subject to a vertical magnetic field aligned with background rotation. In order to gain insight into the convection taking place in the Earth's tangent cylinder…

Fluid Dynamics · Physics 2014-07-04 Kélig Aujogue , Alban Pothérat , Binod Sreenivasan

Understanding solar turbulent convection and its influence on differential rotation has been a challenge over the past two decades. Current models often overestimate giant convection cells amplitude, leading to an effective Rossby number…

Solar and Stellar Astrophysics · Physics 2025-03-12 Quentin Noraz , Allan Sacha Brun , Antoine Strugarek

Magnetic field observations of low-mass stars reveal an increase of magnetic activity with increasing rotation rate. The so-called activity-rotation relation is usually attributed to changes in the underlying dynamo processes generating the…

Solar and Stellar Astrophysics · Physics 2015-06-12 Martin Schrinner