电磁搅拌结晶器钢液流场和温度场模拟仿真

Simulation on Flow Field and Temperature Field of Molten Steel in Bloom Mold with EMS

建立了360 mm×450 mm方坯连铸结晶器电磁搅拌作用下结晶器内钢液流场和温度场的三维数学模型,并应用模型分析了结晶器内钢液流场、温度场的分布特征。结果表明,采用电磁搅拌后,从浸入式水口流出的钢水在电磁搅拌的有效区由垂直向下转变为水平旋转,形成旋转流动的主流区,且在主流区上方的钢水形成由中心向下和由凝固面一侧向上的环流,在主流区下方的钢水形成由凝固面一侧向下和由中心向上的环流。同时,钢水在电磁搅拌作用下流动方向由垂直向下变为水平旋转,使从浸入式水口流出的过热钢水的侵入深度变浅,轴向温度迅速降低,而径向温度升高,凝固前沿的温度梯度增大,有利于传热和促进凝固坯壳的均匀生长。

In order to simulate the flow field and temperature field of molten steel in 360 mm×450 mm bloom continuous casting mold,a 3-D mathematical model was presented.On this basis,the distribution of the flow field and temperature field was analyzed.Numerical simulation results show that the flow direction of molten steel streamed from submerged entry nozzle is changed from vertical downwards to horizontal rotary in effective region of electromagnetic stirring with EMS,and main region of rotary flow is formed.Upper part of molten steel in the effective region is formed into rotary flow from downwards flow of center to upward of solidification surface,then,lower part of molten steel in the effective region is formed into rotary flow from upward part of center to downward of solidification surface.Meanwhile,because of the flow direction changed from vertical downwards to horizontal rotary,the depth of molten steel streamed from submerged entry nozzle becomes shorter,axial temperature becomes lower,radial temperature becomes higher,temperature gradient at solidification surface becomes bigger,and heat transfer becomes more rapidly,which will promote the homogeneous growth of solidifying shell