电磁软接触方坯连铸凝固过程夹杂物碰撞长大行为

Collision and aggregation among inclusions during the billet solidification in the continuous caster with electromagnetic soft-contact

电磁软接触对于方坯连铸而言是一项重要的电磁技术。采用数值模拟方法分析了电磁软接触连铸机内电磁力场、流场和夹杂物场的分布特点。数值结果表明,应用电磁软接触后,电磁力主要集中在靠近结晶器的铸坯表面;电磁力在水口两侧产生涡流,同时加快了液面处钢液的流动。电磁软接触下连铸机内夹杂物分布与无电磁软接触下夹杂物分布大体相似。在结晶器下方,随着距液面距离的增加,夹杂物数量密度逐渐降低,夹杂物特征半径逐渐增大。在液面处,电磁软接触下夹杂物浓度、数量密度和特征半径明显降低。

Electromagnetic soft-contact(EMSC)is one of the important technologies for billet continuous casting.Numerical simulation was applied to analyze the spatial distribution of electromagnetic force field,flow field and inclusion field in the continuous caster with EMSC.Numerical results show that,on the condition of electromagnetic soft-contact,the electromagnetic force focuses on the surface of the billet near the mold.Electromagnetic force results in the two small recirculation zone on both side of the nozzle,and speeds up the fluid flow near the free surface.The spatial distribution of inclusion on the condition of EMSC is almost similar to that on the condition of no EMSC.Under the mold,with the increase of the distance from the free surface,the inclusion concentration and the inclusion number density decrease gradually,but the inclusion characteristic radius increase gradually.With the help of EMSC,the inclusion concentration,number density and characteristic radius decrease obviously near the free surface.