电流频率对连铸圆坯流场-温度场影响的模拟研究

Simulation Research on Effect of Current Frequency on Flow Field and Temperature Field of Continuous Casting Round Billet

以φ430 mm的圆坯为实验对象,采用磁场传输方程和k-ε双方程模型对钢液的流场和温度场进行耦合数值模拟,分析有、无电磁搅拌的情况下,结晶器内钢液的流场和温度场分布情况,进一步改变电流频率,分析在不同电流频率下的流场和温度场分布情况。模拟结果表明:施加电磁搅拌时,迫使结晶器纵向截面内的钢液出现上、下两对回流区,其回流方向相反,钢液在水平截面内做旋转运动;铸坯芯部温度降低,高温区域范围缩小,热区位置上移;电流频率增大时,下回流区开始形成,上回流区位置升高。

Taking round billet with φ430 mm as experiment object, the magnetic field transport equation and k-ε equation were adopted to establish the coupled model of flow field and temperature field, the flow field and temperature field of molten steel in crystallizer with and without electromagnetic stirring were analyzed. The flow field and temperature field under different current frequency were investigated. The simulation results show that, when applying electromagnetic stirring, upper and lower two pairs of backflow area appear in the molten steel on crystallizer longitudinal section. On the contrary backflow direction, the molten steel present rotational motion in the horizontal section. The temperature of slab center decrease, the range of high temperature area reduce and the hotspot location moves up. When the current frequency increase, the down-reflux area begin to form and the location of up-reflux area elevates.