气体流量及水口底部形状对板坯结晶器内流场影响的水模型试验

采用1:1水模型研究了气体流量（010 L/min）和水口底部形状（凹底和尖底）对结晶器内流场的影响。在结晶器断面为230mm×1 200 mm,浇铸速度为1.6 m/min的模拟工况条件下,凹底水口其流体形态优于尖底水口;在结晶器液面波动稳定性方面凹底水口亦优于尖底水口;气体流量在08 L/min,使用尖底水口的流体其表面流速明显高于使用凹底水口的流体;对凹底水口而言,气体流量超过8 L/min,其流体表面流速低于0.2 m/s;120炉IF钢生产结果表明,使用优化的凹底水口和吹氩流量7 L/min,浇铸过程结晶器液面波动在±3 mm以内,铸坯夹杂物比优化前降低24%。

Water Model Examination on Effect of Gas Flow Rate and Nozzle Bottom Shape on Flow Field in Slab Mold

The effect of gas flow rate (0 - 10 L/min) and nozzle bottom shape ( concave bottom and pyramid bottom) on flow field in mold has been studied by using 1: 1 water model. In condition of mold section 230 mm x 1 200 mm and casting speed 1. 6 m/min the fluid pattern in mold with using concave bottom nozzle is better than that with using pyramid bottom nozzle ； and the stability of liquid level in mold with using concave bottom nozzle is also better than that with using pyramid bottom nozzle; with gas flow rate 0 ?8 L/min, the liquid surface velocity with using pyramid bottom nozzle is obviously higher than that with using concave bottom nozzle ； for using concave bottom nozzle as gas flow rate is larger than 8 L/min, its surface velocity is lower than 0. 2 m/s； 120 heats IF steel commercial production results show that using optimized concave bottom nozzle with argon flow rate 7 L/min the fluctuation of surface of liquid in mold during casting precess is within ± 3 mm, and compared with before optimization the inclusions amount in casting slab decreases by 24%.