摘要
浸入式水口结构从根本上决定了结晶器内的钢液流动形式,采用物理模拟和数值模拟方法研究了水口结构及铸坯断面尺寸对板坯结晶器流动行为的影响。通过解析速度云图、表面流速、液面波动、冲击深度及保护渣覆盖情况等特征参数,对结晶器内钢液流动行为进行多角度定量表征。结果表明,水口侧孔倾角向上对1 600 mm×220 mm断面结晶器流场液面扰动较大,其倾角向下15°时射流冲击深度较大,倾角向下8°时最为适宜。水口底部形状会影响钢液的湍动能耗散及流场对称性,对比后得出凹底水口为最佳水口形状。侧孔形状对表面流速影响较小,但对自由液面波动有显著影响,可能导致钢液裸露;当水口侧孔面积一致时,矩形侧孔水口条件下的结晶器液面裸露面积小于跑道形侧孔和方形侧孔情况。而在浇注不同断面尺寸时,仅通过改变水口结构和使用工艺难以获得合理的结晶器流场,还需要借助其他控制流动的手段来推动未来板坯多元化生产的发展。本研究可为改善板坯质量提供理论与工艺指导。
The structure of the submerged entry nozzle(SEN)fundamentally determines the pattern of molten steel flow in the mold.The influence of SEN structure and slab section size on metallurgical behavior of slab mold was studied by physical simulation and numerical simulation.By analyzing the characteristic parameters such as velocity contour,surface velocity,liquid level fluctuation,impact depth and slag coverage,the flow behavior of mold was quantitatively characterized from multiple angles.The results show that liquid level of 1600 mm×220 mm section mold flow field is disturbed greatly when the inclined angle of nozzle port upward,while the impingement depth of jet is larger at the inclined angle downward 15°,and the most suitable angle is downward 8°.The bottom shape of nozzle will affect the turbulent kinetic energy dissipation and flow field symmetry of molten steel,and the concave bottom nozzle is the best.The shape of SEN port has little effect on the surface velocity,but it has a significant effect on the free liquid level fluctuation,which may leads to the exposure of molten steel.When the area of the SEN port is the same,the exposed area of mold liquid surface for rectangular SEN port condition is smaller than that of the raceway and square SEN port situations.When the section size is different,it is difficult to obtain reasonable mold flow field only changing the nozzle structure and using process,so it is necessary to use other instruments for controlling flows to promote the development of diversified slab production in the future.This study can provide theoretical and process guidance for improving slab quality.
作者
陈希青
雷琳琳
宋异
肖红
王璞
冯文文
张家泉
CHEN Xiqing;LEI Linlin;SONG Yi;XIAO Hong;WANG Pu;FENG Wenwen;ZHANG Jiaquan(School of Metallurgical and Ecological Engineering,University of Science and Technology Beijing,Beijing 100083,China;Technical Research Institute,MCC Capital Engineering&Research Incorporation Limited,Beijing 100176,China;Magnetoelectric Research Institute,Hunan Zhongke Electric Co.,Ltd.,Yueyang 414000,Hunan,China)
出处
《中国冶金》
CAS
CSCD
北大核心
2023年第12期42-55,共14页
China Metallurgy
基金
湖南省科技人才托举工程项目(2023TJ-Z14)。
关键词
板坯结晶器
浸入式水口
物理模拟
数值模拟
断面尺寸
slab mold
submerged entry nozzle
physical simulation
numerical simulation
section size
