Numerical Simulation On Behavior Of Metal Jet And The Interface Of Steel Slag Under Magnetic Field

Electromagnetic flow control is a necessary technology in slab continuous casting process, especially for thin slab casting process. In this process, the nozzle jet and interface behavior of molten steel and slag are closely related to the slab quality. In this paper, using the ANSYS CFX software and VOF model, the author investigated the characteristics of the jet and its influence on jet impacting behavior against the wall and the interface of molten steel and slag.In the absence of magnetic field, metal jet flow has the long rang and width of jet close to the narrow surface of mold is large. After imposed electromagnetic brake, metal jet has short range, width of jet close to the narrow surface of mold is small. There is a clear hierarchy and characteristics of valley in slag-metal interface, three partitions occuers clearly in the steel-slag interface. With increased magnetic flux density, the value of wall shear stress is reduced in narrow face of mold. The impact range of metal jet on narrow face of mold is small, the impact location moves up and impact strength of jet on wide face of mold is increased. The reasonable control of magnetic flux density can avoid jet expansion on the wide surface. Only in reasonable magnetic flux density, we can obtain stable deformation on steel-slag interface and inhibit slag entrapment into liquid metal.As the location of magnetic core reduces, the impacting strength and range of metal jet on the wide face of the mold get large. The vertical magnetic field can significantly weaken jet impacting on narrow face of mold, increase jet impacting strength and range on wide face of mold. Reasonable magnetic flux density should be determined by simultaneously considering the impacting of jet on wide and narrow face. Steel/slag interface is consistent with the characteristics of flow field, and inappropriate magnetic field position will result in slag entrapment.With the increasing jet angle, the impact range of metal jet on either side of the wide face of mold is decreased, and the impact strength is increased. Reasonable jet angle should be determined by simultaneously considering the impact of jet on wide and narrow face. With the increasing jet angle, the stability of steel flow in mold and interface both get worse.