The mathematical model of coupling fluid flow, heat transfer, solidification, solute transport, and the electromagnetic field of the bloom in the upper part of the strand was established with three nozzle types. Then, the flow field, distribution of the temperature, solidification, and macrosegregation of carbon were investigated and compared by numerical modeling. In the case of the straight submerged entry nozzle (SEN), the molten steel flows down deep into the liquid pool, and the depth of the jet flow reaches about 1.0 m beneath the meniscus. The jetting zone is the high-temperature zone. In the case of two-port SEN and four-port SEN, the flow patterns and distribution of temperature in the central longitudinal section are similar. The jet flow impinges directly on the initially solidified shell and then it is divided into two longitudinal circulations. The heat of molten steel is dissipated along with the longitudinal circulations. The negative segregation band was generated near the bloom surface due to the washing effect by the rotating flow at the solidification front with three nozzle types. The negative segregation deteriorates gradually with the number of ports decreasing.

用三种喷嘴类型建立了耦合流体流动，传热，凝固，溶质输运和钢绞线上部水华电磁场的数学模型。然后，通过数值模型研究并比较了碳的流场，温度分布，凝固和宏观偏析。对于直入式浸入式喷嘴（SEN），钢水向下深深地流入液池，射流的深度达到弯液面下方约1.0 m。喷射区是高温区。在二端口SEN和四端口SEN的情况下，中央纵向截面中的流动模式和温度分布相似。射流直接撞击在最初凝固的壳体上，然后分成两个纵向循环。钢水的热量与纵向循环一起消散。由于在三种喷嘴类型的凝固前沿的旋转流的洗涤作用，在大方坯表面附近产生了负偏析带。负隔离随着端口数量的减少而逐渐恶化。