脉冲磁致振荡对纯铝熔体电磁力和流场影响的数值模拟

Numerical Simulation of Effect of Pulse Magneto-oscillation on Magnetic Force and Flow Field of Pure Aluminum Melt

在金属熔体周围的环绕线圈中,通入窄脉宽高频交变脉冲电流可以细化其凝固组织,这种组织细化方法称为脉冲磁致振荡。采用ANSYS有限元软件研究脉冲磁致振荡对纯铝熔体电磁力和流场的影响,主要包括线圈脉冲电流峰值,铸件直径及线圈尺寸位置等参数。模拟结果显示,脉冲电流峰值增加,熔体感应的电磁力也随着增大,振荡效果增强。铸件直径增大,电磁力驱使的内部流动效果会减弱。线圈尺寸增大,感应电磁力和熔体流动均增强。线圈下部的电磁力与流动分布导致晶粒的细化效果会优于上部。

The width with high frequency alternating narrow pulse current gets into the coil around the melt to refine the solidification microstructures, which is named pulse magneto-oscillation. The effect of pulse magneto-oscillation on magnetic force and flow field of pure aluminum melt were simulated by the finite element software ANSYS. The parameters include peak value of pulse current, diameter of the melt, the coil size and position. The results show that the induced magnetic force increases as the peak value of pulse current increasing, so effect of ocsillation is increased. While the diameter of melt increases, the flow inside the melt weakens. As coil size increases, the magnetic force and flow get enhanced. When the coil is in the lower position, the induced magnetic force and flow can lead to better grain refinement than the upper position.