大圆坯连铸结晶器电磁偏心搅拌的数值模拟

建立了描述大圆坯连铸结晶器电磁搅拌过程电磁场的三维数学模型,并采用实测数据对模型的准确性进行了验证.研究了不同搅拌电流强度和频率下,磁感应强度与电磁力的变化规律,并重点分析了偏心搅拌下磁感应强度和电磁力的分布特点.结果表明:磁感应强度和电磁力均随搅拌电流强度的增大而增强;随着搅拌电流频率的增大,磁感应强度逐渐减弱,而电磁力先增强后减弱,并在2.5 Hz时达到最大值;偏心搅拌时,电磁力在铸坯横截面上仍呈周向分布,但电磁力和磁感应强度的大小都出现了不对称分布,在靠外弧的一侧更大.

Numerical Simulation of Electromagnetic Field in a Round Bloom Continuous Casting Mould with Eccentric Electromagnetic Stirring

A three-dimensional mathematical model was developed to study the electromagnetic field in a round bloom continuous casting mould with electromagnetic stirring (M-EMS). The simulation results of electromagnetic field were validated by the measured data from the experiments. The effects of stirring current intensity and frequency on magnetic flux density and electromagnetic force were investigated， and the electromagnetic field characteristics were also discussed after applying eccentric M-EMS. The results show that both magnetic flux density and electromagnetic force increase with increasing current intensity. When the stirring current frequency increases， the magnetic flux density decreases and the electromagnetic force increases first and then decreases with the maxima at 2.5Hz. Under the conditions of eccentric M-EMS， the electromagnetic force still appears to be circumferential distribution on the planes transverse to the strand. However， the magnitudes of both magnetic flux density and electromagnetic force show asymmetrical distribution， which are much larger at the side near the external arc of the continuous caster.