Elliptical instability of a flow in a rotating shell

Laurent Lacaze (1) , Patrice Le Gal (1) , Stéphane Le Dizès (1)

1 IRPHE - Institut de Recherche sur les Phénomènes Hors Equilibre

A theoretical and experimental study of the spin-over mode induced by the elliptical instability of a flow contained in a slightly deformed rotating spherical shell is presented. This geometrical configuration mimics the liquid rotating cores of planets when deformed by tides coming from neighboring gravitational bodies. Theoretical estimations for the growth rates and for the non linear amplitude saturations of the unstable mode are obtained and compared to experimental data obtained from Laser D\"{o}ppler anemometry measurements. Visualizations and descriptions of the various characteristics of the instability are given as functions of the flow parameter.

Domaines: Mécanique des fluides [physics.class-ph]; Mécanique des fluides [physics.class-ph]

Laurent Lacaze, Patrice Le Gal, Stéphane Le Dizès. Elliptical instability of a flow in a rotating shell. Physics of the Earth and Planetary Interiors, 2005, 151, pp.194-205. ⟨hal-00014488⟩