title: Instabilities in electromagnetic quasilevitation.
abstract: We investigate free-surface instabilities occurring in various industrial processes involving liquid metal. Of particular interest is the behavior of the free surface of a pool of liquid metal when it is submitted to an alternating magnetic field. Experimentally, we study the effect of a vertical alternating medium-frequency magnetic field on an initially circular pool. We observe various types of behavior according to magnetic field amplitude, e.g., axisymmetric deformations, azimuthal mode structures, slow radial oscillation of the pool perimeter, and random rotation of the pool around its center. Drop rotation could be attributed to nonsymmetric shape deformations. The effect of oxidation leads to drastic changes in pool behavior. The experimental results are then compared to a linear stability analysis of the free surface of a circular liquid drop.
authors.affiliation: Department of Mathematics, University of Waikato, Hamilton, New Zealand and SIMAP/EPM Laboratory, Grenoble Polytechnic Institute, Grenoble, France.
authors.forename: Kirk
authors.initials: K
authors.lastname: Spragg
authors.affiliation: SIMAP/EPM Laboratory, Grenoble Polytechnic Institute, Grenoble, France.
authors.forename: Sebastien
authors.initials: S
authors.lastname: Letout
authors.affiliation: SIMAP/EPM Laboratory, Grenoble Polytechnic Institute, Grenoble, France.
authors.forename: R
authors.initials: R
authors.lastname: Ernst
authors.affiliation: Department of Mathematics, University of Waikato, Hamilton, New Zealand.
authors.forename: Alfred
authors.initials: A
authors.lastname: Sneyd
authors.affiliation: SIMAP/EPM Laboratory, Grenoble Polytechnic Institute, Grenoble, France.
authors.forename: Yves
authors.initials: Y
authors.lastname: Fautrelle