板坯连铸电磁制动下结晶器内金属流场的数学物理模拟

Numerical and Physical Simulation on Flow in Mold with EMBr in Continuous Casting of Slab

采用雷诺时均湍流模型并结合水银物理模拟实验,研究不同磁场配置下板坯结晶器内的金属流动规律,并以此分析不同磁场配置对工艺过程的影响.结果表明:雷诺应力模型(Reynolds stress model,RSM)能够较准确地反映电磁制动(electromagnetic braking,EMBr)下金属流场的变化,该变化引起水口射流及其对结晶器窄边冲刷强度的改变;在全幅二段电磁制动下,上部磁场对液面水平速度和湍动性的抑制作用明显,但从化渣和降低冲击深度的工艺要求来看,上部磁场强度不宜过大.

Combined with a mercury experiment, a Reynolds time-average model was applied to investigate the effects of magnetic flux density on flow in the mold cavity with different electromagnetic braking （EMBr） and on the process. The results show that the Reynolds stress model （RSM） can accurately reflect flow changes of the mold with EMBr. Nozzle jet profile and washing intensity to the .thin wall of mold are varied with alteration of magnetic flux density. The upper portion of the magnetic field can obviously inhibit the surface horizontal velocity and turbulence. However, considering the melting of powder and impingement depth, the upper portion of the magnetic flux density should not be too high.