07底吹气体对FTSC中间包流体动力学的影响(中文）8-26.docVIP

底吹气体对FTSC中间包流体动力学的影响 （东北大学材料与冶金学院辽宁 沈阳 110004）摘要：本文以FTSC中间包为原型，建立了1：2.5的物理模型，研究了传统控流装置（堰、坝和湍流控制器）、底吹气相互组合方式对中间包内流体的影响。实验评价指标包括由停留时间分布曲线（RTD）分析所得的最小停留时间、活塞流体积分率、全混流体积分率和死区体积分率。通过加入示踪剂（高锰酸钾溶液）的方法显示中间包内的流场。传统的堰坝组合方式可以较好地优化中间包流场，但是为了减少耐火材料质控流装置的使用以减小污染钢液的机会，本文提出尝试采用底吹气体替代堰坝来优化流场。实验结果表明，安装在FTSC中间包注流区的双效冲击板（DEP）和下游的导流坝可以很大程度上优化流体的流动状况；中间包底部呈“鞋跟”状，可以在保证铸坯质量的前提下，减少中间包余钢量，提高钢水收得率。底吹气体均有利于在中间包内形成循环流，导流坝可以很好地阻止底部击穿流。停留时间等参数受底吹气体的组合方式影响显著，采用底吹气体代替堰坝组合后，流体在中间包内的停留时间和死区体积分率参数与传统堰坝组合方式相近。特别要指出的是，在导流坝上方设置气幕的实验效果最显著，其死区体积分率降至9%，远小于其它的组合方式。实验结果表明，采用底吹气体取代传统堰坝组合在改善中间包流体流动方面是可行的，适应高效连铸的要求。 关键词：FTSC；中间包；控流装置；底吹气体；物理模拟 Effects of the Gas Injection on the Dynamics of Molten Steel Flowing in FTSC Tundish JIANG Mao-fa, QU Tian-peng (School of Materials and Metallurgy, Northeastern University, Shenyang 110004, China) Abstract: In this paper, the effect of traditional modifiers (such as weir, dam, turbulent inhibitor), gas injection and their combinations on the molten steel flowing dynamics in a FTSC tundish was investigated in a scaled physical model (1:2.5) by determining the flow patterns characteristics parameters (including minimum residence time, volume fractions of plug, perfect mixed and dead flow obtained from the RTD (Residence Time Distribution) curve) and tracer dispersion (KMnO4 Solution). The configuration, position and size of the above flow modifiers and gas flow rate were varied during the process of the study. The fluid flow characteristic parameters could be optimized using the traditional modifiers. Furthermore, it was attempted to replace the traditional modifiers by the gas injection curtain in terms of reducing use of refractory materials. The results showed that the flow control devices of double effect pad (DEP) and dam in the FTSC tundish had a significant influence on improving the flow field and the “Heel” bottom in the outlet region had a great effect on the improvement of metallurgical recovery rate. For all combinations including gas blowing, gas injections we