Modification of bubble-driven liquid metal flows under the influence of a DC magnetic field

Abstract

The paper presents an experimental study devoted to a bubble-driven liquid metal flow under the influence of an external DC magnetic field. Experiments have been performed on laboratory scale at ambient temperature using the ternary alloy GalnSn. Measurements of the bubble-driven liquid metal flow have been carried out using the Ultrasound Doppler Velocimetry (UDV). The magnetic field has been imposed either in vertical direction parallel to the main bubble motion or in horizontal direction, respectively. Whereas a global damping of the flow field was generally observed in the case of the vertical aligned magnetic field, the application of a horizontal magnetic field can provoke a restructuring of the flow pattern with strong, non-steady vortical structures. This finding could attain relevance for metallurgical engineering, for instance the control of the mould flow during the continuous casting of steel by means of an electromagnetic brake. © 2007 ISIJ.