Physical and numerical simulation of flow control for submerged entry nozzle in slab continuous casting
CHEN Xiqing1, LEI Linlin2, SONG Yi3, XIAO Hong3, WANG Pu1, FENG Wenwen1, ZHANG Jiaquan1
1. School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, China; 2. Technical Research Institute, MCC Capital Engineering & Research Incorporation Limited, Beijing 100176, China; 3. Magnetoelectric Research Institute, Hunan Zhongke Electric Co., Ltd., Yueyang 414000, Hunan, China
Abstract：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 1 600 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.
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2023, Vol. 33 
