不同水口类型下的宽板坯结晶器流场特征数值模拟研究

Numerical simulation of flow field characteristics of wide slab mold with different types of water inlet

随着连铸机向着超宽、超厚的设计方向发展,重新评估极端条件下的连铸结晶器流场特征显得十分必要,基于国内后续可能的超宽板坯连铸设计,针对较大断面3300 mm×180 mm结晶器流动开展了数值模拟,研究了3种典型板坯连铸水口下的结晶器流动特征。结果表明:两孔水口结晶器的流场形态呈经典双环流流动模式,五孔水口结晶器增加了水口处和中轴处钢液的扰动,CSP型水口结晶器的流场形态呈自下而上的大环流;五孔水口结晶的液面波动既保证了液面波动在安全数值范围内,又增加了对弯月面流动死区的扰动,对流场的优化效果显著;五孔水口典型的结构参数如下:主侧孔倾角为10°~20°,插入深度为150~160 mm,主副孔间距为10~20 mm。

With the development direction of ultra-wide and ultra-thick design of caster,it is necessary to re-evaluate the flow field characteristics of casters under extreme conditions.Based on the probable future designs of ultra-wide slab caster in China,the numerical simulation is established for the flow of molds with large cross-section of 3300 mm×180 mm,and the flow characteristics of molds with three typical slab continuous casting nozzles were studied.The results show that the flow field of the two-orifice nozzle mold is a classical double-circulation flow pattern,while the five-orifice nozzle mold increases the disturbance of the molten steel at the nozzle and the central axis.The flow field of the CSP-type water port casting mold is a large bottom-up circulation.The fluctuation of the liquid level of the five-orifice water orifice not only ensures the fluctuation of the liquid level within the safe value range,but also increases the disturbance of the flow dead zone of the meniscus,whose optimization effect of the flow field is remarkable.The typical structural parameters of the five-hole water outlet are as follows:the angle of the main side hole is 10°-20°,the insertion depth is 150-160 mm,and the distance between the main and secondary holes is 10-20 mm.