Numerical Simulation On Melt Flow And Heat Transfer In Continuous Casting Mold With EMBr

As the last step of continuous casting process,the flow pattern of molten steel in mold can significantly affect the quality of slabs.At present,applying electromagnetic braking（EMBr）to control the molten steel flow and slab solidification in mold under different working conditions is widely used in improving the uniformity of temperature distribution and promoting the uniform growth of solidified shell.However,the electromagnetic braking process belongs to the strong coupling process of multiple physical fields involving magnetic,flow and temperature field,which makes the process crucial but complex.Therefore,in order to explore the flow and heat transfer of molten steel in the mold with EMBr,this paper mainly studies the three-dimensonal electromagnetic field distribution,and molten steel jet flow characteristics,heat transfer and solidification behavior with Ruler EMBr.In current research,the effects of magnetic flux density,magnetic pole position and submerged entry nozzle（SEN）angle on the flow and heat transfer of molten steel in mold are analyzed and discussed.The main results are as follows:（1）The static magnetic field generated by the horizontal magnetic pole of Ruler EMBr is distributed in a“runway”shape.The magnetic flux density gradually decreases by gradient from the center of horizontal magnetic pole to surrounding area.The magnetic flux density at the free surface and the outlet of mold,both of which are far away from the action area of the magnetic field,are reduced to about 0.02 T.（2）When the magnetic flux density is less than 0.2 T,the molten steel flow in the upper reflux area of mold can not be well controlled.However,when the magnetic flux density reaches 0.3 T,the electromagnetic force generated by the horizontal magnetic pole significantly inhibits the diffusion of the main section of the turbulent jet to the narrow face of mold,and effectively control the flow in the upper reflux area by reducing the maximum velocity of free surface to 0.197 m·s^-1.（3）When the position of the horizontal magnetic pole is H₁=225 mm,the electromagnetic force generated by the horizontal magnetic pole can effectively control the impact of the upper reflux molten steel on the free surface and inhibit the diffusion of molten steel jet to the narrow face of mold.Therefore,the surface flow velocity of molten steel is reduced,which can help to prevent surface slagging phenomenon.Moreover,the uniform growth of solidified shell at the narrow face is promoted,so that the adhesion between the solidified shell and mold at the narrow face is prevented.In general,the results of this paper can provide a theoretical reference for optimizing the metallurgical effects of EMBr.