Effective Removal Zone of Inclusions in a Horizontal Channel under A.C. Magnetic Field Imposition

Abstract

A channel type horizontal induction heating tundish compensates for the heat loss of the molten steel due to Joule loss generated by an A.C. magnetic field. It also exhibits another function of inclusions removal because the A.C. magnetic field generates an electromagnetic pinch force. For the inclusions below the center of the horizontal channel, the direction of the electromagnetic pinch force and the buoyancy force acting on them are opposite. Thus, there is a possibility of the existence of the balanced position where the magnitudes of the electromagnetic pinch force and the buoyancy force are same. Around there the net time average force acting on the inclusions is almost zero, and there is a dead zone where the removal time of the inclusions under the imposed A.C. magnetic field is longer than that without it. In this study, non-dimensional models of the force balance and the inclusion trajectory were established and numerically solved to find out the relationship between the dead zone and the A.C. magnetic field parameters because the dead zone range should be reduced for effective removal of the inclusions. Consequently, the dead zone range decreased with the increase in the magnetic field intensity. Furthermore, the shielding parameter of 5–10 is one of the optimum conditions to reduce the dead zone range under the constant magnetic field condition because the dead zone range has the local and/or global minimum at this parameter.