电磁搅拌对连铸结晶器内钢液流动的影响

Effect of Electromagnetic Stirring on Liquid Steel Flow in Continuous Casting Crystallizer

为了研究电磁搅拌对连铸结晶器内钢液流动的作用效果,利用有限元数值模拟方法研究并探讨了不同电流频率、电流强度作用下的奥氏体不锈钢S30432小方坯连铸结晶器内磁感应强度、电磁力、流场以及流速的分布和变化情况。研究结果表明:电磁场的主要作用范围集中在电磁搅拌器内部区域,磁感应强度和电磁力随着电流强度的增加而增大,随着电流频率的增加先增大后减小,磁感应强度和电磁力的最大值分别出现在铸坯表面和近表面靠近磁轭的位置;电磁搅拌能够显著增强结晶器内钢液的纵向回流效果,有利于促进夹杂物浮回钢液表面,便于除气除渣净化钢液;电磁搅拌作用的施加,能够降低水口流入钢液的冲击深度,增强钢液在水平方向的流动,扩大钢液高流速区域,有利于钢液内部及表面的换热,从而,提高晶粒细化效果。

In order to study the effect of electromagnetic stirring on the flow of molten steel in the continuous casting crystallizer,the finite element numerical simulation method was used to study and discuss the distribution and change of magnetic induction intensity,electromagnetic force,flow field and flow velocity in the continuous casting crystallizer of austenitic stainless steel S30432 billet under different current frequency and current intensity.The results show that the main action range of electromagnetic field is concentrated in the internal area of electromagnetic stirrer.The magnetic induction intensity and electromagnetic force increase with the increase of current intensity,and increase first and then decrease with the increase of current frequency.The maximum values of magnetic induction intensity and electromagnetic force appear on the surface of slab and near the surface near the yoke,respectively.Electromagnetic stirring can significantly enhance the longitudinal reflux effect of molten steel in the mold,which is conducive to promoting the floating of inclusions back to the surface of molten steel,and is convenient for degassing and slag removal to purify molten steel.At the same time,the application of electromagnetic stirring can reduce the impact depth of the nozzle into the molten steel,enhance the flow of the molten steel in the horizontal direction,expand the high flow rate area of the molten steel,which is conducive to the internal and surface heat transfer of the molten steel and improve the grain refinement effect.