插钉法研究板坯连铸结晶器液面特征

Nail board experiments to investigate level characteristic in slab continuous casting mold

采用可以同时获取板坯连铸结晶器内弧侧、厚度方向中心面和外弧侧液面信息的插钉板,通过在结晶器内连续插取,研究了板坯连铸结晶器液面特征。得到了结晶器内不同时刻、不同位置处液面高度;发现了连铸生产过程中内、外弧侧液位有差异,提出了对称流不仅只是以水口为中心结晶器左右两侧流场的对称,还应包括以结晶器厚度方向中心面为中心,内弧侧与外弧侧流场的对称;预测了该工况下结晶器内液面波动较大以及卷渣发生频率较高的位置为水口附近和窄面与宽度方向1/4之间液面流速较大的部位;验证了插钉试验不仅可以获得连铸结晶器内的液面流速,还可通过多次插钉试验研究液面波动特征,在传统的物理模拟和数值模拟方法之外提出了一种直接、接触式测量连铸结晶器液面轮廓进而研究液面波动的方法。

The level characteristic including level fluctuation and surface velocity has been studied by nail board experiments. The nail board is made of three rows of nails which can simultaneously get the information of loose side,center in thickness and fixed side in slab continuous casting mold. Based on this,the heights of level at different instants of time and different position are obtained. Main results find that there is a little difference in fluid flow between loose side and fixed side during casting. In another word,the surface flow between loose side and fixed side in the mold is asymmetric.As a further consequence,symmetric flow includes not only the flow in width taking SEN as symcenter,but also the flow in thickness taking half of thickness as centerline. The resluts validate the feasibility using nail board experiments to study both the surface velocity and the level fluctuation and can predict the position where entrapment of mold powder happens.This work proposes a method of contact measuring through which level profile can be measured directly and provides a possibility for studying the level characteristic in slab continuous casting mold besides traditional method,water model and CFD model.