旋转电极电渣重熔过程熔滴滴落及熔池形状的模拟

Numerical simulation of droplet behavior and pool shape in ESR with rotating electrode

建立了瞬态三维耦合数学模型以探索旋转电极对电渣重熔过程中电磁场、流场、温度场和熔池形状的影响。通过求解麦克斯韦方程组得到电磁场的相关信息,利用VOF方法描述金属熔滴的运动,采用焓-多孔介质模型计算凝固过程。当电极旋转,金属熔滴在离心力作用下,从电极边缘抛出,增加了金属熔滴在渣池中停留的时间与沿途路径,有利于提高电渣重熔工艺的精炼效率。模拟结果表明,随着电极旋转,熔滴数量增多,尺寸变小,渣池内的温度分布变得均匀,当电极的转速由0 r/min提高至20和50 r/min,熔池深度由81 mm降至78和61 mm,熔池形状逐渐变得浅平,有利于提高电渣重熔铸锭的质量。

A transient three-dimensional coupled mathematical model was established to explore the influence of rotating electrode on electromagnetic field, flow field, temperature field and pool shape in ESR process. The information of electromagnetic field was obtained by solving Maxwell equations, the movement of metal droplet was described by VOF method, and the solidification process was calculated by enthalpy porous medium model. When the electrode rotates, the metal droplets are thrown out from the edge of the electrode under the action of centrifugal force, which increases the residence time and path of the metal droplets in the slag pool, and improves the refining efficiency of ESR process. The simulation results show that as the electrode rotates, the number of droplets increases, the size becomes smaller, and the temperature distribution in the slag pool becomes uniform. When the electrode rotating speed increases from 0 r/min to 20 r/min and 50 r/min, the depth of the molten pool decreases from 48 mm to 43 mm and 27 mm, the shape of the molten pool gradually becomes shallow and flat, which is conducive to improving the quality of ESR ingot.