SEN底部形状对结晶器内钢液流场和温度场的影响

Effect of Bottom Structure of Submerged Entry Nozzle on Flow Field and Temperature Field in Continuous Casting Mold

针对某钢厂板坯连铸结晶器及浸入式水口(SEN)的结构参数,建立了描述结晶器内钢液流动的三维数学模型,应用FLUENT软件对结晶器内钢液的流场和温度场进行耦合计算,分析SEN底部形状对结晶器内流场和温度场的影响,并利用水模试验对钢液的流动行为进行了验证。结果表明:凸底水口出口附近钢液的速度较大,流股的冲击深度较大,使结晶器内高温区下移,不利于凝固坯壳的生长;平底水口自由面速度较大、温度较高,有利于保护渣的熔化,但易产生液面裸露现象;凹底自由面速度较小、温度较低,有利于液面稳定。

Based on the structure parameters of mold and submerged entry nozzle,i, e SEN, for slab continuous casting in some steel plant, a 3-D numerical model describing the flow of liquid steel in mold was carried out. Commercial software FLUENT was used to simulate coupling flow field and temperature field of the molten steel. The effects of bottom structure of SEN on the flow field and temperature field of molten steel were analyzed and com- pared, moreover, the flow field results were validated by the water model. The research results indicate that near the outlet of convex SEN, the molten steel velocity is relatively high and the impact depth is deep, which enable high temperature region to shift down and go against the growth of solidified shell, the free surface velocity and temperature of flat bottom SEN is relatively high, which is beneficial for mold flux melting but can lead to naked molten steel, the free surface velocity and temperature of concave SEN velocity is relatively low, which is beneficial for the liquid level stabilizing. These research results can be used for the design of SEN as reference.