电磁搅拌作用下弧形结晶器流场的数值模拟

研究了双侧孔浸入式水口条件下，弧形结晶器内流场受电磁搅拌作用的影响。建立了圆坯连铸结晶器电磁搅拌过程的电磁场和流场数学模型，分别采用有限元和有限体积法进行数值求解，讨论不同电参数下结晶器内流场分布特点。结果表明：电磁力在水平面沿圆周方向呈非对称分布，竖直面上呈“中间大，两头小”分布；电磁搅拌作用使得结晶器内流场除出现上回流区外，还产生主回流区和下回流区，促进钢水流动，有利于等轴晶的形成和热传递；励磁电流强度是影响电磁搅拌作用的主要因素，频率的影响效果有限，最佳搅拌参数是[I＝200 A，][f＝3 Hz。]

Numerical simulation on flow field in curved mold with electromagnetic stirring

The influence of the electromagnetic stirring on the distribution of the flow field in the curved mold with two-sideimmersed nozzle is analyzed. A three-dimensional mathematical model to represent electromagnetic field and flow field in the round bloom mold with electromagnetic stirring is established， and solved by the finite element method and finite volume method， respectively. The effects of the different current and frequency value of coils on the behavior of flow field are discussed. The results show that the electromagnetic force distributes circumferentially as well as asymmetrically at horizontal plane， and the electromagnetic force is bigger at the center at vertical plane of stirrer. Owing to the effect of electromagnetic stirring， the recirculation zones formed at the center as well as the bottom in the curved mold， which promotes the flow of the molten steel and contributes to the formation of the equiaxed crystal and heat transfer. The exciting current intensity plays an important role in the effect of the electromagnetic stirring， and the frequency has some limited effectiveness. The most suitable stirring parameters are[I＝200 A，][f＝3 Hz.]