影响RH循环流量的行波磁场工艺参数分析

Analysis of Technological Parameters of Traveling Magnetic Field Affecting Circulation Flow Rate in RH

建立了交变电磁场下气液两相流动的数学模型,考察了不同励磁电流参数下行波磁场对循环流量的影响。计算结果表明:电磁力的垂直分量与行波运动方向一致,水平分量呈中心对称。在励磁电流强度为200A,频率为10Hz的条件下,磁场分别单独作用于上升管或下降管时循环流量可提高10%以上,同时作用于上升管和下降管时循环流量可提高20%左右;当吹氩量小于1750L/min时,在上升管处施加磁场的效果优于下降管;当吹氩量大于1750L/min时,二者效果相同。当磁场作用于上升管时,在励磁电流频率为10Hz的条件下,电流强度由100A提高到600A,循环流量可由83t/min增大到129t/min,并且近似成正比例关系;当磁场作用于上升管时,在励磁电流强度为200A的条件下,电流频率由10Hz增大到60Hz,循环流量先增大后减小,在30Hz达到极大值,为91.4t/min。

A mathematical model about the gas-liquid multiphase flow on the condition of the alternating electromagnetic field was developed to investigate the effect of different exciting current parameters on the circulation flow rate in RH degasser. The numerical results indicate that the vertical electromagnetic force has the same direction as the traveling magnetic field, while the level electromagnetic force is centrosymmetric. On the condition of 200 A of exciting current density and 10 Hz of current frequency, the circulation flow rate is up more than 10 percent by imposing the traveling magnetic field on the up snorkel, while the circulation flow rate is up about 20 percent by imposing the traveling magnetic field on the up snorkel and the down snorkel. The circulation flow rate in the case of the traveling magnetic field near the up snorkel is greater than that in the case of the traveling magnetic field near the down snorkel when the gas flow rate is less than 1 750 L/min. But such a difference disappears when the gas flow rate is greater than 1750 L/min. If the exciting current frequency is 10 Hz and the magnetic field is imposed on the up snorkel, the circulation flow rate increases from 83 t/min to 129 t/min linearly when the current density increases from 100 A to 600 A. If the exciting current density is 200 A and the magnetic field is imposed on the up snorkel, the circulation flow rate increases firstly and then decreases when the current frequency increases from 10 Hz to 60 Hz and there is a maximum value of 91.4 t/min when the current frequency is 30 Hz.