Turbulent kinematic dynamos in ellipsoids driven by mechanical forcing

Abstract

Dynamo action in planetary cores has been extensively studied in the context of convectively-driven flows. We show in this letter that mechanical forcings, namely tides, libration and precession, are also able to kinematically sustain a magnetic field against ohmic diffusion. Previous attempts published in the literature focused on the laminar response or considered idealized spherical configurations. In contrast, we focus here on the developed turbulent regime and we self-consistently solve the magnetohydrodynamic (MHD) equations in an ellipsoidal container. Our results open new avenues of research in dynamo theory where both convection and mechanical forcing can play a role, independently or simultaneously.

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Cited by in corpus (9)

• Experimental study of the non-linear saturation of the elliptical instability: inertial wave turbulence versus geostrophic turbulence
• Turbulent viscosity acting on the equilibrium tidal flow in convective stars
• Fossil field decay due to nonlinear tides in massive binaries
• Acoustic and inertial modes in planetary-like rotating ellipsoids
• Precession-driven flows in stress-free ellipsoids
• Kinematic dynamos in triaxial ellipsoids
• Zonal flows driven by libration in rotating spherical shells: the case of periodic characteristic paths
• Geophysical flows over topography, a playground for laboratory experiments
• Did lunar tides sustain the early Earth's dynamo?