连铸结晶器内气泡运动行为及影响因素

摘要

An original mathematical model was developed to study the behavior of bubbles and influence factors in continuous casting mold. The interactions between bubbles were considered in the model, including bounce off, coalescence and breakup. The effects of casting speed and nozzle immersion depth on bubbles behavior were investigated, including region of bubble dispersion, gas volume fraction and bubble mean diameter. The results showed that the initial bubbles can merge into a large bubble in the nozzle. With increasing the nozzle immersion depth, the region of bubble dispersion and gas volume fraction increase, but the average diameter of bubbles decreases under the same casting speed. With increasing casting speed, the law is same under the same nozzle immersion depth. Casting speed has greater influence than nozzle immersion depth on bubble diameter.%为了研究连铸结晶内气泡的运动行为及影响因素,采用了改进的数学模型对气泡在钢液内的运动行为进行了模拟.数学模型考虑气泡的弹开、聚合以及破碎行为,分析了不同拉速和浸入深度对气泡分布范围、含气率以及气泡平均直径的影响.研究结果表明:初始直径较小的氩气泡在水口内的运动过程中会发生碰撞聚合,生成大气泡.相同拉速下,气泡的分布范围和含气率随着水口浸入深度的增加而增大,气泡平均直径随浸入深度的增大而减小.相同浸入深度下,气泡的分布范围和含气率随着拉速的增加而增大,气泡平均直径随拉速的增大而减小.拉速对气泡直径的影响大于浸入深度的影响.