Magneto-inertial waves in a rotating sphere
Résumé
Hydromagnetic oscillations have been observed in recent spherical Couette flow experiments with liquid sodium. In the Derviche Tourneur Sodium (DTS) installation in Grenoble, where the imposed magnetic field is dipolar, they are supposed to be magneto-inertial waves with azimuthal wavenumbers ranging from 1 to 7, and azimuthally propagating in a retrograde way with regard to the rotating fluid. A new numerical simulation code has been developed in order to calculate such magneto-inertial waves in spherical geometry and in the presence of an external magnetic field. A few known examples are first considered in order to validate this code, then preliminary results are obtained in the DTS geometry.