Abstract Micro-bubbles were generated using gas injection through tiny orifices located at the upper part of the ladle shroud, for deep cleaning the liquid steel. An impact pad was employed to improve the dispersion of micro-bubbles in the liquid bath, reduce the collision between bubbles, as well as to achieve the conventional functions of a turbulent inhibitor. A 3-D numerical modeling was developed to predict the flow characteristics and bubble motion behaviors under the effect of the impact pad, with the bubble sizes obtained from the measurements in full-scale water experiments. For comparison, the corresponding numerical simulation was also carried out in the tundish with a conventional turbulent inhibitor. It was found that the impact pad promotes the spreading of micro-bubbles in the tundish bath, which could effectively reduce the coalescence of bubbles, so as to restrain the secondary bubble grow-up. The global efficiency of inclusion removal by bubble flotation was evaluated, considering the mechanism of repeated bubble sweeps in each element. The inclusion removal was raised by 14.33–37.09% due to the extended area of bubbles dispersion, even with the same bubble amount and size.

中文翻译：

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使用缓冲垫的三角形中间包中微气泡的运动行为

摘要 微气泡是通过位于钢包罩上部的微小孔口注入气体产生的，用于对钢水进行深度清洗。缓冲垫被用来改善微气泡在液浴中的分散，减少气泡之间的碰撞，以及实现湍流抑制剂的常规功能。开发了 3-D 数值模型来预测冲击垫作用下的流动特性和气泡运动行为，气泡尺寸从全尺寸水实验中的测量中获得。为了进行比较，还在带有常规湍流抑制剂的中间包中进行了相应的数值模拟。发现冲击垫促进了中间包浴中微气泡的扩散，可有效减少气泡的聚结，从而抑制二次气泡的长大。考虑到每个元素中重复气泡扫描的机制，评估了气泡浮选去除夹杂物的整体效率。由于气泡分散区域的扩大，即使气泡数量和尺寸相同，夹杂物去除率也提高了 14.33-37.09%。