Tian Yushi, Zhou Haichen, Wang Guobin, Xu Lijun, Qiu Shengtao, Zhu Rong
School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing (USTB), Beijing 100083, China.
National Engineering Research Center of Continuous Casting Technology, Central Iron and Steel Research Institute, Beijing 100081, China.
Materials (Basel). 2023 Aug 17;16(16):5665. doi: 10.3390/ma16165665.
In the current study, the transient flow characteristics on the top surface of a steel slab continuous casting strand were numerically investigated using a large eddy simulation combined with volume of fluid (LES + VOF) model. The validation of numerical simulation was verified via nail board measurement in the industrial continuous casting mold. The effects of casting speed on the top surface level profile and the instantaneous distribution of vortex were discussed. The level variation profile migrated after a period of time, moving from one side of the wide face of the mold to the other. The wave height and transient variation degree of the standing wave increased with an increase in the casting speed. The region near the SEN was more likely to promote the formation of vortices. The vortex generation became easier when the vorticity peaks were concentrated on the outer edge of the low-speed confluence area near the submerged entry nozzle. In addition, the effect of surface velocity on the instantaneous level fluctuation was analyzed. The frequency of level fluctuations was highest at 34 mm, and the high-frequency range of velocity fluctuation was 2060 mm/s at 0.9 m/min casting speed for a 1500 mm × 200 mm caster section. The linear relationship between the level fluctuation and surface velocity magnitude was obtained. The present work aimed at evaluating the dynamic problem of the standing wave at the liquid powder-molten steel interface on the top surface of the mold, which is helpful in optimizing the casting parameters for regular casting practice and improving the quality of the steel slabs.
在当前研究中，采用大涡模拟结合流体体积（LES + VOF）模型对钢坯连铸铸坯顶面的瞬态流动特性进行了数值研究。通过工业连铸结晶器中的钉板测量验证了数值模拟的有效性。讨论了浇铸速度对顶面液位轮廓和涡旋瞬时分布的影响。液位变化轮廓在一段时间后发生迁移，从结晶器宽面的一侧移动到另一侧。驻波的波高和瞬态变化程度随着浇铸速度的增加而增大。 SEN附近的区域更易促进涡旋的形成。当涡度峰值集中在浸入式水口附近低速汇合区的外边缘时，涡旋生成变得更容易。此外，分析了表面速度对瞬时液位波动的影响。对于1500mm×200mm的铸机断面，在浇铸速度为0.9m/min时，液位波动频率在34mm时最高，速度波动的高频范围为2060mm/s。得到了液位波动与表面速度大小之间的线性关系。本工作旨在评估结晶器顶面液渣 - 钢液界面处驻波的动力学问题，这有助于优化常规浇铸实践中的浇铸参数并提高钢坯质量。
