6 papers
Magnetohydrodynamic drag on an oscillating sphere in a rotating spherical cavity
David Cébron, Paolo Personnettaz
The drag on an oscillating sphere is a classical fluid-mechanics problem, yet no existing theory simultaneously accounts for confinement, rotation, viscosity and magnetic fields. W…
Semi-convection in rotating spherical shells: flows, layers and dynamos
Paul Pružina, Nathanaël Schaeffer, David Cébron
Large regions of giant planets are thought to possess unstable thermal gradients stabilised by gradients in heavy-element composition. The fluid can then develop semi-convection, a…
Ohmic and viscous damping of inner core translational oscillations
Paolo Personnettaz, David Cébron, Nathanaël Schaeffer +2
Large earthquakes can trigger translational oscillations of Earth's inner core (Slichter modes), yet their damping remains uncertain. Using simulations, we quantify viscous and Ohm…
Did lunar tides sustain the early Earth's dynamo?
Jérémie Vidal, David Cébron
Geological data show that, early in its history, the Earth had a large-scale magnetic field with an amplitude comparable to the one of the present geomagnetic field. However, its o…
Planetary dynamos driven by semiconvection in stably stratified layers
Paul Pružina, David Cébron, Nathanaël Schaeffer
Stably stratified fluid layers are common in gaseous planets, stellar interiors, and planetary cores, and have long been considered incapable of sustaining dynamo action. Here, we…
Geophysical flows over topography, a playground for laboratory experiments
Jérémie Vidal, Jérôme Noir, David Cébron +4
Physicists face major challenges in modelling multi-scale phenomena that are observed in geophysical flows (e.g. in the Earth's oceans and atmosphere, or liquid planetary cores). I…