Lorentz body force induced by travelling magnetic fields

M. P. Volz¹ - K. Mazuruk²

¹ NASA Marshall Space Flight Center, Huntsville, AL 35812, USA }
² University of Alabama in Huntsville, Huntsville AL 35899, USA

Abstract
The Lorentz force induced by a travelling magnetic field (TMF) in a cylindrical container has been calculated. The force can be used to control flow in electrically conducting melts and the direction of the magnetic field and the resulting flow can be reversed. A TMF can be used to partially cancel a flow driven by buoyancy. The penetration of the field into the cylinder decreases as the frequency increases, and there exists an optimal value of frequency, for which the resulting force is a maximum. Expressions for the Lorentz force in the limiting cases of low frequency and infinite cylinder are also given and compared to the numerical calculations. Figs 7, Refs 5.