气泡去除夹杂物的机理

Mechanism on Inclusion Removal by Bubble

针对非金属夹杂物引起的钢材质量问题,用高速摄像仪和图像处理软件对结晶器水模内的空气泡去除夹杂物模拟粒子的行为和机理进行了研究。结果表明,粒子通过粘附去除,俘获过程分为5个子过程,即粒子向气泡靠近并发生碰撞、粒子与气泡粘附形成液膜、液膜减到足够薄后破裂形成新的气固接触界面、粒子滑移到气泡底部、两者处于动态的稳定状态一起上浮。粒子在气泡表面上滑移时处于不稳定状态,气泡受到轻微扰动,粒子会失稳脱离液膜。

Aiming at the quality defect caused by non-metallic inclusions in the steel,the motion and mechanism study on the inclusion removal by the bubble in the water model of slab continuous casting mold were investigated by using high speed video and image processing software.The results show that the particle in inclusion simulation is attached to remove by bubble.The attachment process can be decomposed into 5 sub-processes which the particle approaches and collides the gas bubble,the thin film of liquid between the particle and the bubble is formed,the new interface of gas-solid appears after the thin film decreases to less than a critical thickness and ruptures,the particle slips to the bottom on the bubble surface,and the particle follows the bubble in dynamic and stable state to floating up finally.While the particle on the bubble surface slips in unstable state,the particle can detach from the bubble surface as the bubble is disturbed slightly.