Optimization of flow field in 1 270 mm×150 mm slab mold by dissipative submerged entry nozzle
WANG Yang1, MA Dangshen1, YANG Maosheng1, LI Jingshe2, YANG Shufeng3
1. Special Steel Research Institute, Iron and Steel Research Institute Co.,Ltd.,Beijing 100081, China; 2. School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, China; 3. State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, Beijing 100083, China
Abstract:Aiming at the problem of liquid level fluctuation in the production of 1 270 mm × 150 mm slab mold in a steel plant, the structure of the submerged entry nozzle was improved, and the influence of improved submerged entry nozzle on flow field of the mold was analyzed. The results show that the flow field distribution in the mold is more reasonable after the improvement of nozzle, and the surface velocity decreases. The maximum free-surface velocity decreases from 0.414 m/s to 0.365 m/s, a decrease of 11.8%. The particle image velocimetry (PIV) results are consistent with the numerical calculation results of velocity field distribution, confirming the reliability of the numerical calculation results. Finally, water simulation experiments were conducted on the fluctuation of mold oil layer by the prototype nozzle and the improved dissipative nozzle respectively. The research results show that the thickness of the thinnest oil layer under different casting speeds after using dissipative nozzle is much greater than that of the prototype nozzle, which can stably cover the liquid surface without exposing. When the casting speed increases to 2.0 m/min, the thinnest oil layer thickness of the prototype nozzle is only 0.005 m, while the thinnest oil layer thickness is still 0.015 m when using the new dissipative nozzle. Dissipative nozzle can effectively reduce the fluctuation of free-surface and prevent the reoxidation occurrence of molten steel. The research results can provide reference for optimizing the structure of mold nozzle.
王杨, 马党参, 杨卯生, 李京社, 杨树峰. 耗散型浸入式水口对1 270 mm×150 mm板坯结晶器流场优化[J]. 中国冶金, 2023, 33(10): 65-72.
WANG Yang, MA Dangshen, YANG Maosheng, LI Jingshe, YANG Shufeng. Optimization of flow field in 1 270 mm×150 mm slab mold by dissipative submerged entry nozzle[J]. China Metallurgy, 2023, 33(10): 65-72.
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