钢圆坯连铸过程中渐开式电磁旋流水口数值模拟  

NUMERICAL SIMULATION OF SWIRLING FLOW IN DIVERGENT SUBMERGED ENTRY NOZZLE IN ROUND BILLET CONTINUOUS CASTING OF STEEL

作　　者：李德伟[1] 苏志坚[1] 陈进[1] 王强[1] 丸川雄净[1] 赫冀成[1] 

机构地区：[1]东北大学材料与冶金学院,沈阳110819

出　　处：《金属学报》2013年第7期871-880,共10页Acta Metallurgica Sinica

基　　金：中央高校基本科研业务费项目N100409010;高等学校学科创新引智计划项目B07015;辽宁省高校重点实验室支持计划项目LS2010065资助~~

摘　　要：提出了一种新的浸入式水口内产生旋流的方法.即在水口外施加可移动的旋转电磁场,非接触地形成钢液旋流.为进一步发挥旋流作用,采用渐开式水口,对圆坯连铸中浸入式水口及结晶器内钢液流场、温度场进行了三维数值模拟,并重点研究了水口渐开角度结合不同旋流强度对结晶器内流场及温度场的影响.研究结果表明,浸入式水口内磁场和旋流速度随着线圈电流强度的增加而增加.当电流强度为500 A,频率为50 Hz时.可产生最大为3 m/s左右的旋流速度.当水口采用同一渐开角度,随着旋流强度的增大,水口出流的冲击深度减小,上返流增强,弯月面温度提高.但当旋流强度增大到一定程度后,结晶器内弯月面附近温度变化不大.采用同一旋流强度,随着水口渐开角度的增加,结晶器内水口出口上方的上返流先增强后减弱,在渐开角度为60°时,上返流最强.同样,弯月面附近温度也是先提高后有所降低,在渐开角度为60°时,弯月面温度最高.水口渐开角度为60°,线圈电流350 A,频率为50 Hz时,在水口入口处施加0.5 m/s水平速度的人工偏流后,电磁旋流能对该偏流进行有效的抑制.With the development of continuous casting technology, the quality of billet has been paid more and more attention recently. It is very important in continuous casting to strictly control the cleanliness of molten steel, and to reduce the defects of billet. The control of flow pattern of molten steel in mold is one of the important means to increase casting efficiency and improve billet quality. Swirling flow in the submerged entry nozzle （SEN） has great effect on improving the uniformity and stability of the outflow from the nozzle in continuous casting of steel process. A new process for swirling flow generation in the SEN has been proposed. That is a rotating electromagnetic field is set up around the SEN to induce swirling flow in it by Lorentz force. In this research, the flow and temperature fields in the SEN and round billet mold with electromagnetic swirling are numerically simulated. The effects of the divergent angle of the SEN with electromagnetic swirling on the flow and temperature fields in the mold are investigated. The simulated results show that, with the increase of the coil current intensity, the magnetic flux density and the swirling flow velocity in the SEN increases. The largest swirling flow velocity in the SEN can reach about 3 m/s in coil current intensity 500 A, frequency 50 Hz. In a divergent angle of the SEN, such as 60℃, when the coil current intensity increases, the impinging depth of the outflow from the nozzle reduces, the upward flow velocity and the meniscus temperature increase. While the coil current intensity increases larger than 350 A, the meniscus temperature changes little. In a certain intensity of swirling flow, such as 350 A, 50 Hz, when the divergent angle of the SEN increases, the upward flow velocity and the meniscus temperature firstly increase and then decrease. In divergent angle 60℃, the upward flow velocity and meniscus temperature get the largest value. In a divergent angle 60℃, coil current intensity 350 A, frequency 50 Hz, with an artificial uneven

关 键 词：连铸 电磁旋流 浸入式水口 结晶器 数值模拟 

分 类 号：TF777.1[冶金工程—钢铁冶金]