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Related papers: The dynamo bifurcation in rotating spherical shell…

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We investigate numerically the self-sustained dynamo action in a spinning sphere whose sense of rotation reverses periodically. This system serves as a simple model of a dynamo in small bodies powered by frequent collisions. It is found…

Geophysics · Physics 2015-06-18 Xing Wei , Rainer Arlt , Andreas Tilgner

Choosing a simple class of flows, with characteristics that may be present in the Earth's core, we study the ability to generate a magnetic field when the flow is permitted to oscillate periodically in time. The flow characteristics are…

Geophysics · Physics 2009-11-10 Ashley P. Willis , David Gubbins

In planetary fluid cores, the density depends on temperature and chemical composition, which diffuse at very different rates. This leads to various instabilities, bearing the name of double-diffusive convection. We investigate rotating…

Fluid Dynamics · Physics 2019-09-04 Rémy Monville , Jérémie Vidal , David Cébron , Nathanaël Schaeffer

The numerical simulations of planetary dynamos still operate in a regime very far from the planets. For example, it seems unlikely that viscous forces are at all significant in planetary interiors, yet some of the simulations display a…

Earth and Planetary Astrophysics · Physics 2015-06-18 P A Davidson

In the inclined layer convection system, thermal convection in a Rayleigh--B\'enard cell tilted against gravity, the flow is subject to competing buoyancy and shear forces. For varying inclination angle ($\gamma$) and Rayleigh number…

Fluid Dynamics · Physics 2026-05-26 Zheng Zheng , Sajjad Azimi , Florian Reetz , Tobias M. Schneider

We construct a five-mode helical dynamo model containing three velocity and two magnetic modes and solve it analytically. This model exhibits dynamo transition via supercritical pitchfork bifurcation. We show that the critical magnetic…

Fluid Dynamics · Physics 2017-08-22 Rohit Kumar , Pankaj Wahi

The paper deals with a problem of interaction between hydrodynamics and mechanics of nonlinear elastic bodies. The existence question for two-dimensional symmetric steady waves travelling on the surface of a deep ocean beneath a heavy…

Analysis of PDEs · Mathematics 2008-12-02 Pietro Baldi , John F Toland

Double-diffusive convection driven by both thermal and compositional buoyancy in a rotating spherical shell can exhibit a rather large number of behaviours often distinct from that of the single diffusive system. In order to understand how…

Fluid Dynamics · Physics 2020-04-28 Luis Silva , James F. Mather , Radostin D. Simitev

We investigate numerically kinematic dynamos driven by flow of electrically conducting fluid in the shell between two concentric differentially rotating spheres, a configuration normally referred to as spherical Couette flow. We compare…

Earth and Planetary Astrophysics · Physics 2012-08-07 Xing Wei , Andrew Jackson , Rainer Hollerbach

Recently, eigenmodes of rotating fluids, namely inertial modes, have received much attention in relation to their destabilization when coupled to gravitational radiation within neutron stars. However, these modes have been known for a long…

Astrophysics · Physics 2008-11-26 Michel Rieutord

To understand the generation of the Earth's and planetary magnetic fields, we investigate numerically the combined effect of precession and convection on the dynamo action in a spherical shell. The convection alone, the precession alone and…

Earth and Planetary Astrophysics · Physics 2016-08-24 Xing Wei

Snap-buckling is a rapid shape transition in slender structures, appearing as a fundamental switching mechanism of natural and man-made systems. Boundary conditions of structures are crucial to predict and control their snap-buckling…

Soft Condensed Matter · Physics 2026-01-23 Takara Abe , Tomohiko G. Sano

A study is reported of the quantum scattering resonances of dissociating molecules using a semiclassical approach based on periodic-orbit theory. The dynamics takes place on a potential energy surface with an energy barrier separating two…

Chemical Physics · Physics 2016-04-12 Pierre Gaspard

The shape assumed by a slender elastic structure is a function both of the geometry of the space in which it exists and the forces it experiences. We explore by experiments and theoretical analysis, the morphological phase-space of a…

Soft Condensed Matter · Physics 2023-12-11 S Ganga Prasath , Joel Marthelot , Rama Govindarajan , Narayanan Menon

We study dynamo action using numerical simulations of planar Boussinesq convection at rapid rotation (low Ekman numbers, Ek), focusing on subcritical dynamo action in which the dynamo is sustained for Rayleigh numbers, Ra, below the…

Fluid Dynamics · Physics 2020-11-13 Robert G. Cooper , Paul J. Bushby , Celine Guervilly

We study the ageing properties of the semi-infinite kinetic spherical model at the critical point and in the ordered low-temperature phase, both for Dirichlet and Neumann boundary conditions. The surface fluctuation-dissipation ratio and…

Statistical Mechanics · Physics 2009-11-11 Florian Baumann , Michel Pleimling

We present an attempt to reach realistic turbulent regime in direct numerical simulations of the geodynamo. We rely on a sequence of three convection-driven simulations in a rapidly rotating spherical shell. The most extreme case reaches…

The core of a terrestrial-type planet consists of a spherical shell of rapidly rotating, electrically conducting, fluid. Such a body supports two distinct classes of quasi-geostrophic eigenmodes: fast, primarily hydrodynamic, inertial modes…

Geophysics · Physics 2014-07-25 Elisabeth Canet , Chris Finlay , Alexandre Fournier

Rayleigh-B\'enard convection in rotating spherical shells can be considered as a simplified analogue of many astrophysical and geophysical fluid flows. Here, we use three-dimensional direct numerical simulations to study this physical…

Fluid Dynamics · Physics 2016-11-23 T. Gastine , J. Wicht , J. Aubert

The dynamical systems of planet-belt interaction are studied by the fixed-point analysis and the bifurcation of solutions on the parameter space is discussed. For most cases, our analytical and numerical results show that the locations of…

Astrophysics · Physics 2015-06-24 Ing-Guey Jiang , Li-Chin Yeh