直流电对金属液电磁净化的影响

推导了矩形管通电金属液的感应磁场,基于磁流体力学方程组,数值计算了二维金属液诱生流场,并追踪了夹杂物颗粒在流场中的运动轨迹.结果表明,金属液的感应磁场不可忽视,其诱生流场干扰了外加磁场下夹杂物的正常迁移,电磁净化宜采用扁管和圆管;同时,利用感应磁场的自约束性,单电流可实现金属液的电磁净化.

EFFECTS OF DIRECT CURRENT ON ELECTROMAGNETIC PURIFICATION FOR LIQUID METALS

Based on the induced magnetic field of the conducted melt in a rectangular pipe,the 2-dimensional flow field is computed,then the inclusion trajectories are obtained by solving the MHD equations and the particle trajectory equations,respectively.Results show that the induced magnetic field is apt to produce convection in a square pipe,and thus to disturb the inclusion migration.To avoid it,the pipe with rectangular or circular cross section is better to be applied than one with square cross section for the electromagnetic purification.On the other hand,the induced magnetic field has an in built tendency of self limit,which makes it possible to remove inclusion from liquid melts only with currents (DC or AC) rather than with extra magnetic fields.