冶金过程旋涡流动行为模拟研究

Modeling of vortex flow during metallurgical process

连铸钢包浇注末期出现的旋涡卷渣现象对连铸钢水质量具有重要影响。以相似原理为基础,构建了相似比为1∶10的钢包模型,对钢包浇注过程中旋涡形成及卷渣过程进行了系统模拟研究。分析了钢包出口尺寸与偏心率、顶渣厚度与黏度对旋涡形成过程的影响规律。研究结果表明(:1)钢包出口尺寸和布置位置对于旋涡形成过程影响显著。出水口位置不变的情况下,临界旋涡高度随着出口通径增大而增加;同一出口直径条件下,临界旋涡高度随着出口偏心率的增加而逐渐降低,并且获得最佳出口位置为0.75 R(;2)浇注初期的初始切向流速越大,临界起旋高度越高。通过增加顶渣厚度或增加顶渣黏度的方法可以有效抑制旋涡流动。为了有效抑制旋涡流动,改变出口位置和调整顶渣物性均是可以付诸实施的有效途径。

Cleanness of molten steel in tundish is closely related to the slag entrapment by vortex at end of ladle teeming process.Based on the similarity criteria,series water modeling experiments,whose scale was 1∶10,have been carried out to investigate the formation and evolution mechanisms of vortex in ladle during teeming process.The effect of exit dimension and location,slag thickness and viscosity on critical height of vortex were studied.It came to the conclusions as follow.(1)Under the present experimental conditions,the exit diameter and location played important role for vortex evolution.The critical height of vortex formation decreased with decreasing of exit diameter and with increasing of exit eccentricity,the best value of that was 0.75 R.(2)By changing the thickness and viscosity of modeling slag and inhibiting initial tangential speed of fluid flow in ladle,the critical vortex height decreases monotonously.In order to control vortex flow,this paper provide an effective method,such as changing exit location or adjusting slag properties.