大圆坯连铸M-EMS参数对磁场和流场分布的影响

采用有限元法和有限体积法对φ250mm大圆坯连铸结晶器电磁搅拌(M-EMS)磁场和流场进行耦合计算。分析了不同电磁搅拌电流和频率下磁场和流场的分布。研究表明,数值模拟结果与实测结果基本一致。钢液中心面的磁感应强度在角部要明显大于中心。电磁力在横截面周向上分布均匀,流动呈涡旋状。当频率相同时,磁感应强度、电磁力和流速随着电流的增加而增加。当电流相同时,沿拉速方向,磁感应强度随频率增加而减小,电磁力和流速随频率的增加而增加。沿搅拌器中心径向,磁感应强度和电磁力随频率增加而减小,频率对切向流速的影响不大。对于φ250mm大圆坯连铸结晶器电磁搅拌,在电流和频率为480A,3Hz时能起到良好的搅拌效果。

Influence of M-EMS Parameters on Distribution of Magnetic Field and Flow Field in Continuous Casting Mold of Bloom

A coupled numerical simulation with finite element method and finite volume method was conducted based on φ250 mm bloom during continuous casting with mold electromagnetic stirring.The influence of EMS current and frequency on distribution of magnetic field and flow field was studied.The comparison shows that the calculated results are basically consistent with the experimental data.On the center surface of EMS,magnetic flux density in the corner is significantly greater than that in the center.Electromagnetic force is uniform in circumferential and flow like vortex.At the same frequency,magnetic flux density,electromagnetic force and velocity all increase with the current.At the same current,in the casting direction,magnetic flux density decreases with the increase of frequency,but electromagnetic force and velocity increase with the frequency.In the radial of EMS,magnetic flux density and electromagnetic force decrease with the increase of frequency,the influence of frequency on tangential velocity is very little.For φ250 mm bloom during continuous casting with mold electromagnetic stirring,the current and frequency of 480 A,3 Hz have good stirring effect.