Instabilities of MHD flows driven by traveling magnetic fields

Reddy, K. Sandeep; Fauve, S.; Gissinger, Christophe

doi:10.1103/physrevfluids.3.063703

Cited by 5 publications

(4 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These results of an efficiency bounded by and decreasing with the level of turbulence are surprisingly similar to the one obtained by Reddy et al. (2018) in a very different MHD set-up, suggesting some universal behaviour of the energy budget of electromagnetically driven flows.…”

Section: Flow Regimes and Transition To Turbulencesupporting

confidence: 89%

“…Because conducting fluids can either dissipate energy viscously or by ohmic dissipation, the question of the energy budget of such electromagnetically driven flows is highly non-trivial. In electromagnetically driven flows, the energy equation is (Reddy, Fauve & Gissinger 2018) where , (respectively ) is the total kinetic (respectively magnetic) energy, (respectively ) is the viscous (respectively ohmic) dissipation; is the term which couples the two equation and corresponds to the transfer of energy between the two fields and is the injected power.…”

Section: Flow Regimes and Transition To Turbulencementioning

confidence: 99%

See 1 more Smart Citation

Turbulence in electromagnetically driven Keplerian flows

et al. 2021

View full text Add to dashboard Cite

show abstract

Section: Flow Regimes and Transition To Turbulencesupporting

confidence: 89%

Section: Flow Regimes and Transition To Turbulencementioning

confidence: 99%

Turbulence in electromagnetically driven Keplerian flows

et al. 2021

View full text Add to dashboard Cite

show abstract

“…Magnetohydrodynamic (MHD) fluids play a vital role in kinetics and their applications have been extensively studied (Brushlinskii & Zhdanova 2004;Chkhetiani, Eidelman & Golbraikh 2006;Nickeler, Goedbloed & Fahr 2006;Frewer, Oberlack & Guenther 2007;White & Hazeltine 2009;Kuiroukidis 2010;Tsui et al 2011;Cicogna 2012;Zahid et al 2013;Cicogna & Pegoraro 2015;Kuiroukidis & Throumoulopoulos 2016;Reddy, Fauve & Gissinger 2018). An important application of the MHD model is the study of equilibrium.…”

Section: Introductionmentioning

confidence: 99%

General three-dimensional equilibria for gravitating ideal magnetohydrodynamics of field-aligned steady incompressible flows with an application to solar prominences

Moawad

2020

J. Plasma Phys.

View full text Add to dashboard Cite

This paper investigates the motion of three-dimensional ideal magnetohydrodynamics with incompressible flows. The governing equation is performed at steady state, with the magnetic field parallel to the plasma flow. The equations of stationary equilibrium are derived and described mathematically in Cartesian space. Two approaches for derivation of general three-dimensional solutions for Alfvénic and non-Alfvénic flows at constant and variable fluid densities are constructed. The general vector and scalar potentials of the velocity field are used to derive general formulas of general three-dimensional solutions for Alfvénic and non-Alfvénic flows. To verify the general results we have obtained, some examples are presented. An application that may be of interest for coronal loops and solar prominences is presented.

show abstract

“…This expression of the Lorentz force is well known in the context of electromagnetic pumps 17,18 , and describes how a small driving of the ocean is produced as long as σ is finite. An important feature is the phase lag φ l between the Jovian field B 0 and the induced one, which controls the torque applied on the ocean.…”

mentioning

confidence: 95%

A magnetically driven equatorial jet in Europa’s ocean

Gissinger¹,

Petitdemange²

2019

Nat Astron

Self Cite

View full text Add to dashboard Cite

During recent decades, data from space missions have provided strong evidence of deep liquid oceans underneath a thin outer icy crust on several moons of Jupiter 1, 2 , particularly Europa 3, 4 . But these observations have also raised many unanswered questions regarding the oceanic motions generated under the ice, or the mechanisms leading to the geological features observed on Europa 5, 6 . By means of direct numerical simulations of Europa's interior, we show here that Jupiter's magnetic field generates a retrograde oceanic jet at the equator, which may influence the global dynamics of Europa's ocean and contribute to the formation of some of its surface features by applying a unidirectional torque on Europa's ice shell.Whereas both radiogenic and tidal heating 8, 9 produce the energy dissipation necessary to the melting of the ice 10, 11 , motions in the ocean underneath the Jovian moons are believed to be generated through vigorous thermal convection 12 , hydrothermal plumes 13, 14 or double-diffusion convection 15 . Such flows certainly play a dominant role, but may fail at explaining some of the observations if considered alone 9 , strongly suggesting the presence of an additional physical mechanism in these oceans. Because the magnetic dipole axis is tilted by about 10 o with the rotation axis of the gaseous giant, Jupiter's moons also experience a time-varying magnetic field with a rotation rate ω, inducing electrical currents in the oceanic salty water 16 .Here, we argue that as long as the phase lag between the induced field and the Jovian one is non-zero, these induced currents naturally combine with the magnetic field to generate a Lorentz force, leading to a weak magnetohydrodynamic (MHD) process that might play a significant role on the global dynamics of the ocean. We therefore model Europa's interior as a spherical shell (mean radius R = (R i + R E )/2, thickness h = R E − R i ) of salty water (electrical conductivity σ and kinematic viscosity ν) confined between an inner mantle of silicate rocks (radius R i ) and an outer layer (radius R E ) of ice crust (see our Method section for a definition of the control parameters). We specifically model Europa here, but our results should apply equally to subsurface oceans 1

show abstract

Instabilities of MHD flows driven by traveling magnetic fields

Cited by 5 publications

References 26 publications

Turbulence in electromagnetically driven Keplerian flows

Turbulence in electromagnetically driven Keplerian flows

General three-dimensional equilibria for gravitating ideal magnetohydrodynamics of field-aligned steady incompressible flows with an application to solar prominences

A magnetically driven equatorial jet in Europa’s ocean

Contact Info

Product

Resources

About