中文摘要：

利用VOF方法和Lagrange两相流模型描述了吹氩结晶器内钢／渣界面行为，并用水模型实验检验了数值模拟结果．在此基础上考察了吹氩量、拉速，结晶器宽度，水口浸入深度及气泡尺寸对钢／渣界面卷混的影响规律．结果表明：拉速为1．8m／min时，增大吹氩量，结晶器的上回流区逐渐消失，气泡对界面的扰动则不断加剧；吹氩量一定时，拉速由1．2m／min增至2．2m／min的过程中，气泡的冲击深度增加，氩气泡对钢液流型和界面形状的影响减弱；增加水口浸入深度对抑制吹氩下界面波动作用明显，而结晶器宽度对此影响较小；气泡尺寸显著影响钢／渣界面行为．

英文摘要：

The interfacial behavior between fluid steel and molten slag layer in a slab continuous casting mold with blowing argon gas was described using the VOF （volume of fluid） method and Lagrange multi-phase flow model, and the prediction was validated by the water model. The influences of casting speed, argon gas volume flowrate, mold width, submergence depth of SEN （submerged entry nozzle） and bubble size on interfacial behavior were numerically investigated. The results show that given a casting speed 1.8 m/min, the upper circulating flow in the mold gradually disappears and the interfacial unevenness disturbed by argon bubbles is gradually evident with increasing argon gas flowrate. Raising the casting speed from 1.2 m/min to 2.2 m/min leads to the deeper penetration of bubbles and less influences of argon bubbles on the flow pattern and interfacial profile at a given argon gas flowrate. Increasing the submergence depth of SEN can effectively restrain interfacial oscillations in mold, while mold width has little effect on it. Bubble size has a remarkable influence on the interfacial behavior of molten steel and slag in mold.