真空自耗电弧熔炼中电磁搅拌的数值模拟

Numerical Simulation of Electromagnetic Stirring during Vacuum Arc Remelting

利用ANSYS软件对真空自耗电弧熔炼的电磁搅拌过程进行三维模拟计算,分析重熔电流、磁场和洛伦兹力的分布情况,讨论了搅拌线圈对磁场和搅拌力的影响。结果表明:重熔电流从坩埚壁经熔池表面流回电极,铸锭和坩埚底部几乎没有电流;重熔电流产生环绕对称轴的磁场,磁场强度从电极中心到坩埚外壁呈先增大后减小的趋势;搅拌线圈产生平行于对称轴的磁场,其磁感应强度在铸锭部分呈均匀分布;施加搅拌线圈产生了使熔池发生旋转的洛伦兹力。

In the present paper, 3-D numerical simulations of electromagnetic stirring during vacuum are remelting （VAR） were conducted by using the ANSYS software to study the distribution of remelting current, magnetic field and Lorentz force. The effects of coil on magnetic and Lorensz force were also discussed. The results show that the current flows during VAR from crucible wall to the electrode via the surface of the ingot melt pool, and the currents in the crucible base and the ingot base are almost zero. The magnetic field inducted by remelting current is axisymmetric and rounding, and the magnetic flux density along radial direction increases to a maximum value near the edge of the electrode and then decreases. The magnetic field in ingot inducted by coil is parallel to the symmetry axis and the magnetic flux density is nearly uniform. The Lorentz force of coil could circumrotate the ingot melt pool.