连铸单流中间包钢液非稳态流动行为物理模拟

Physical modeling on unsteady flow behavior of molten steel in single strand tundish

针对非稳态换包过程对钢水洁净度显著恶化问题,基于相似原理,构建了相似比为1∶2的中间包物理模型,对单流中间内钢液非稳态流动行为进行了系统研究。研究结果表明,稳态条件下通过设置尺寸合理的堰坝和湍流控制器可以有效改善中间包内流体的流动状态。非稳态条件下,当钢包换包结束,中间包液位回升过程中,钢液平均停留时间随液位的上升而延长,最长可达497s;死区体积分率随液位回升而逐渐减小,最小降至23.91%。换包过程中液位的降低和回升伴随着流动状态的剧烈波动,最终恶化了非金属夹杂物上浮去除行为。

Aiming at the problem that the unsteady changing process significantly deteriorates the cleanliness of molten steel,aphysical model with a scale ratio of 1∶2 was established to investigate the unsteady flow behavior of molten steel in a single strand tundish based on the similarity principle.The results show that the flow state of the fluid in tundish can be effectively improved by setting reasonable size dam and weir and turbulence controller under steady state condition.In the unsteady condition,when the ladle change is over and the tundish liquid level rises,the average residence time of liquid steel increases with the increase of liquid level,up to 497 s.The dead volume fraction decreases gradually with the liquid level rising,and the minimum value is 23.91%.During the whole ladle change process,the liquid level decreases and rises with the drastic fluctuation of the flow state,which eventually deteriorates the removal behavior of non-metallic inclusions in molten steel.