In order to study the behavior during the mass transfer and homogenization in the molten pool by argon blowing at the bottom of the ladle in the refining process, a LES-DPM-VOF coupled numerical model for a 150 t ladle in a steel plant was established to simulate slag-steel-argon three phase flow, and the effects of argon blowing rates on multiphase flow behavior of slag-steel-argon and the homogenization phenomenon of liquid steel were studied. The results show that the shape of the slag hole predicted by the numerical model is in good agreement with experimental observations. When the blowing rate is 50 L/min, the maximum velocity of molten steel in the ladle is about 0.7 m/s, and the slag-steel interface only shows a little fluctuation without the formation of a slag hole. As the blowing rate increases from 50 L/min to 100 L/min, the lifting effect of bubbles on molten steel is enhanced, and the maximum upward velocity of molten steel increases from 0.7 m/s to 1.07 m/s. In addition, the fluctuation of the slag-steel interface increases. Furthermore, the study on homogenization behavior shows that the homogenization time of the alloy is inversely proportional to the argon blowing rate. When the diameter of the simulated alloy is 20 cm and the blowing rate is 50 L/min, the homogenization time is 245 s. When the blowing rate increases to 300 L/min, the homogenization time decreases to 145 s.
本文基于Explicit算法计算VOF模型方程,离散方法采用Geo-Reconstruct算法,该算法具有几何精度高、计算效率高等优点;采用压力隐式算子分割算法(pressure-implicit with splitting of operators, PISO)进行压力-速度耦合,整个钢包内空气相、钢液相和渣相的厚度分别为175,3 095,70 mm,且控制体积中三相体积分数之和为1.
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