在物理模拟实验的基础上,采用基于标准k-ε湍流模型的三维稳态流动与磁场耦合模型,对电磁制动(electromagnetic braking,EMBr)条件下板坯连铸结晶器中的金属流场进行数值模拟,研究了磁场强度及其分布对结晶器内金属流动的影响,并与物理模拟结果进行了对比,进一步揭示了在物理模拟中受传感器数量等限制所无法观察到的一些细微现象或局部流态及流动行为.结果表明,在流动控制结晶器(flow control mold,FC Mold)电磁制动方式下,结晶器内流场具有复杂的三维特性.此时必须注意结晶器液面流速过慢所导致的表面夹杂、横裂等问题.合适、有效的电磁制动也应与连铸工艺相匹配.
The solidified structures of horizontally continuous casting（HCC） of super-thin slab and its relations with the current were studied under the electromagnetic vibration（EMV）.The results show that,under the action of the periodical forces from EMV,the solidified structures of the super-thin slab of pure tin is greatly refined,and the extent of grain refinement is increased with the magnitude of alternating current.For the Sn-10%Pb alloy,it is shown that the EMV promotes the growth of equiaxed grains in the center of super-thin slab,and the grains are refined with the alternating current increasing.This is useful to prevent some solidification defects in the horizontally continuous casting of super-thin slab,such as columnar grains butting,porosity,inclusions and gases gathering,and composition segregation in the centre of slab.
