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Related papers: Dynamo induced by time-periodic force

200 papers

In magnetohydrodynamic (MHD) turbulence, the large-scale magnetic field sets a preferred local direction for the small-scale dynamics, altering the statistics of turbulence from the isotropic case. This happens even in the absence of a…

Plasma Physics · Physics 2017-05-10 Vladimir Zhdankin , Stanislav Boldyrev , Joanne Mason

We show that in decaying hydromagnetic turbulence with initial kinetic helicity, a weak magnetic field eventually becomes fully helical. The sign of magnetic helicity is opposite to that of the kinetic helicity - regardless of whether or…

The frequency dependence of the interlayer conductivity of a layered Fermi liquid in a magnetic field which is tilted away from the normal to the layers is considered. For both quasi-one- and quasi-two-dimensional systems resonances occur…

Strongly Correlated Electrons · Physics 2009-10-31 Ross H. McKenzie , Perez Moses

With a non local shell model of magnetohydrodynamic turbulence we investigate numerically the turbulent dynamo action for low and high magnetic Prandtl numbers ($Pm$). The results obtained in the kinematic regime and along the way to dynamo…

Astrophysics · Physics 2009-11-13 Rodion Stepanov , Franck Plunian

We show that simple 2 and 3-layer flux-transport dynamos, when forced at the top by a poloidal source term, can produce a widely varying amplitude of toroidal field at the bottom, depending on how close the meridional flow speed of the…

Solar and Stellar Astrophysics · Physics 2015-05-28 Peter A. Gilman , Mausumi Dikpati

We consider the generation of magnetic activity --- dynamo waves --- in the astrophysical limit of very large magnetic Reynolds number. We consider kinematic dynamo action for a system consisting of helical flow and large-scale shear. We…

Solar and Stellar Astrophysics · Physics 2015-06-19 Fausto Cattaneo , Steven Tobias

It is shown that the magnetic current-driven (`kink-type') instability produces flow and field patterns with helicity and even with \alpha-effect but only if the magnetic background field possesses non-vanishing current helicity…

Solar and Stellar Astrophysics · Physics 2015-05-20 Guenther Ruediger , Marcus Gellert , Rainer Arlt

The reflectivity of a highly localized magnetic inhomogeneity is experimentally studied. The inhomogeneity is created by a dc-current carrying wire placed on the surface of a ferrite film. The reflection of propagating dipole-dominated…

Other Condensed Matter · Physics 2009-01-28 T. Neumann , A. A. Serga , B. Hillebrands , M. P. Kostylev

Much work on turbulent three-dimensional dynamos has been done using triply periodic domains, in which there are no magnetic helicity fluxes. Here we present simulations where the turbulent intensity is still nearly homogeneous, but now…

Solar and Stellar Astrophysics · Physics 2019-02-20 A. Brandenburg

Spin waves can induce domain wall motion in ferromagnets. We derive the equations of motion for a transverse domain wall driven by spin waves. Our calculations show that the magnonic spin-transfer torque does not cause rotation-induced…

Mesoscale and Nanoscale Physics · Physics 2017-12-06 Vetle Risinggård , Erlend Grytli Tveten , Arne Brataas , Jacob Linder

We report on the basic properties of recently observed magnetic field resonance, induced time dependent oscillation, and hysteresis effects in the current flowing through two weakly coupled vertical quantum dots at high source-drain bias…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 D. G. Austing , C. Payette , G. Yu , J. A. Gupta

In strongly compressible magnetohydrodynamic turbulence, obliqueness between the large-scale density gradient and magnetic field gives an electromotive force mediated by density variance (intensity of density fluctuation). This effect is…

Solar and Stellar Astrophysics · Physics 2022-05-31 Nobumitsu Yokoi , Steven M. Tobias

A non-linear, time-dependent, magnetically driven dynamo theory which shows how magnetically dominated configurations can relax to become helical on the largest scale available is presented. Coupled time-dependent differential equations for…

Astrophysics · Physics 2009-11-07 Eric G. Blackman , George B. Field

The dynamo effect is the most popular candidate to explain the non-primordial magnetic fields of astrophysical objects. Although many systematic studies of parameters have already been made to determine the different dynamical regimes…

Fluid Dynamics · Physics 2020-07-14 Mélissa D. Menu , Ludovic Petitdemange , Sébastien Galtier

We theoretically investigate pumping of phonons by the dynamics of a magnetic film into a non-magnetic contact. The enhanced damping due to the loss of energy and angular momentum shows interference patterns as a function of resonance…

Mesoscale and Nanoscale Physics · Physics 2018-07-17 Simon Streib , Hedyeh Keshtgar , Gerrit E. W. Bauer

We study the asymptotic properties of a stochastic model for the induction equations of the magnetic field in a three dimensional periodic domain. The turbulent velocity field driving the electromotive force on the magnetic field is modeled…

Probability · Mathematics 2025-06-04 Federico Butori , Eliseo Luongo

A dynamo model is presented, based on a previously introduced kinematic model, in which the reaction of the magnetic field on the mass flow through the Lorentz force is included. Given the base mass flow corresponding to the case with no…

Solar and Stellar Astrophysics · Physics 2018-11-05 Laura Sraibman , Fernando Minotti

Accretion disc turbulence is investigated in the framework of the shearing box approximation. The turbulence is either driven by the magneto-rotational instability or, in the non-magnetic case, by an explicit and artificial forcing term in…

Astrophysics · Physics 2008-11-26 Axel Brandenburg

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

In this review, we describe turbulent drag reduction in a variety of flows using a universal framework of energy flux. In a turbulent flow with dilute polymers and magnetic field, the kinetic energy injected at large scales cascades to the…

Plasma Physics · Physics 2023-01-04 Mahendra K. Verma , Manohar K. Sharma , Soumyadeep Chatterjee