连铸结晶器内弥散氩气泡的瞬态运动和捕捉行为  

Transient movement and capture behavior of dispersed argon bubbles in continuous casting mold

作　　者：宫佳睿 刘中秋 吴颖东 姚毓超 姜玖华 李宝宽 GONG Jiarui;LIU Zhongqiu;WU Yingdong;YAO Yuchao;JIANG Jiuhua;LI Baokuan(School of Metallurgy,Northeastern University,Shenyang 110819,Liaoning,China)

机构地区：[1]东北大学冶金学院,辽宁沈阳110819

出　　处：《钢铁研究学报》2022年第5期461-469,共9页Journal of Iron and Steel Research

基　　金：国家自然科学基金资助项目(51974071,52171031)。

摘　　要：针对连铸结晶器内弥散氩气泡的瞬态运动和捕捉行为,发展了耦合流动-传热凝固-气泡运动的大涡模拟模型,研究了结晶器凝固坯壳内钢液的非稳态湍流场和氩气泡的瞬态运动特征。结果表明,凝固坯壳对结晶器内钢液流场有较大影响,液相区内钢液流动不对称,导致气泡的运动和捕捉位置分布不均匀;小尺寸的气泡更容易运动到液相穴较深的区域;且随着拉速的增加,气泡的穿透深度增大;将使逃逸率和滞留率达到极值时的气泡直径定义为临界直径,本研究中临界气泡直径在0.5~1 mm之间;当气泡直径大于临界气泡直径时,在给定拉速下均有较高的上表面逃逸率,以及较低的坯壳捕捉率和滞留率;而当气泡直径小于临界气泡直径时,坯壳捕捉率和滞留率随着拉速的增大和气泡直径的减小而增大。In order to study the transient movement of the dispersed argon bubbles in the continuous casting mold, a large eddy simulation model coupled with flow-heat transfer and solidification-bubble movement was developed. The unsteady turbulent flow field of molten steel in the solidified shell and the transient motion characteristics of argon bubbles in the mold were studied. The results show that the solidified shell has a great influence on the flow field of molten steel in the mold. Asymmetric flow of molten steel in the liquid phase leads to uneven distribution of bubble movement and capture positions. And small-sized bubbles are more likely to move to the deeper areas of the liquid core, and the penetration depth of the bubble increases with the increase of the casting speed. The critical bubble diameter is defined as the bubble diameters that make the escape rate and retention rate reach the extreme. the critical bubble diameter is between 0.5 and 1 mm. When the bubble diameter is larger than the critical bubble diameter, the upper surface escape rate and the shell capture rate and retention rate are relatively low at a given casting speed;while when the bubble diameter is smaller than the critical bubble diameter, the shell capture rate and the retention rate increases with increasing casting speed and decreasing bubble diameter.

关 键 词：连铸结晶器 氩气泡 瞬态运动 凝固坯壳 捕捉行为 

分 类 号：TF777.1[冶金工程—钢铁冶金]