title: Reduction of velocity fluctuations in a turbulent flow of gallium by an external magnetic field.
abstract: The magnetic field of planets or stars is generated by the motion of a conducting fluid through a dynamo instability. The saturation of the magnetic field occurs through the reaction of the Lorentz force on the flow. In relation to this phenomenon, we study the effect of a magnetic field on a turbulent flow of liquid gallium. The measurement of electric potential differences provides a signal related to the local velocity fluctuations. We observe a reduction of velocity fluctuations at all frequencies in the spectrum when the magnetic field is increased.
authors.affiliation: Laboratoire de Physique Statistique, Ecole Normale Supérieure & CNRS, 24 Rue Lhomond, 75231 Paris Cedex 05, France. mberhanu@lps.ens.fr
authors.forename: Michael
authors.initials: M
authors.lastname: Berhanu
authors.forename: Basile
authors.initials: B
authors.lastname: Gallet
authors.forename: Nicolas
authors.initials: N
authors.lastname: Mordant
authors.forename: Stéphan
authors.initials: S
authors.lastname: Fauve