水口底部形状对高拉速板坯连铸结晶器液面特征的影响  

Effect of nozzle bottom shapes on level fluctuation and meniscus velocity in highspeed continuous casting molds

作　　者：邓小旋[1,2] 熊霄[1] 王新华[1] 李林平[1] 郝晨晖[1] 魏鹏远[1] 季晨曦[2] 

机构地区：[1]北京科技大学冶金与生态工程学院,北京100083 [2]首钢技术研究院,北京100041

出　　处：《北京科技大学学报》2014年第4期515-522,共8页Journal of University of Science and Technology Beijing

摘　　要：采用1：1的水模型和工业试验研究了水口底部形状（凹底、平底和凸底）和凹底水口井深（井深分别为0、10和20 mm）对结晶器流场与自由液面特征的影响.在拉速为1.8 m·;min-1时，凹底水口和平底水口下结晶器内流场的对称性要优于凸底水口.三种水口条件下结晶器液面的表面流速变化规律为凸底水口＆gt;平底水口＆gt;凹底水口.对比不同井深凹底水口的液面特征发现：井深为10 mm的凹底水口可以有效降低结晶器的液面波动与表面流速，防止卷渣的发生.工业试验对比了凹底与凸底水口在实际生产中的使用效果，发现凸底水口下的液面波动显著大于凹底水口.凸底水口下结晶器液面波动变化的功率（频率为0.003~0.05 Hz）比凹底水口大约10倍，这与水模型的结果吻合较好.The effects of the bottom shapes （well-bottom, flat-bottom and mountain-bottom） of submerged entry nozzles （SENs） and the well depth of well-bottom SENs （0, 10 and 20 mm） on the level characteristics of high-speed continuous casting molds were investigated by full scale water modeling and plant trials. Fluid flows in the molds with well-bottom and flat-bottom SENs are more symmetrical than those with mountain-bottom SENs. The decreasing order of meniscus velocity in the molds is from mountain-bottom, flat-bottom to well-bottom SENs. Comparative studies on the level characteristics of the molds between well-bottom SENs with different well depths show that well-bottom SENs with the well depth of 10 mm can decrease the level fluctuation and meniscus velocity, and this is helpful to prevent slag entrapment. Plant trials indicate that level fluctuation in the molds with mountain-bottom SENs is higher than that with well-bottom SENs, and this agrees well with the water modeling results. The power density spectra of level fluctuation using mountain-bottom SENs are about 10 times as large as those using well-bottom SENs at the frequency ranging from 0. 003 to 0. 05 Hz.

关 键 词：连铸 板坯 结晶器 浸入式水口 

分 类 号：TF777.1[冶金工程—钢铁冶金]