旋转磁场作用下真空精炼装置内脱碳过程的模拟研究

Modeling Investigation on Decarburization Process in RH Refining System Under the Action of Rotating Electromagnetic Field

为了了解旋转磁场下真空精炼装置内的脱碳反应,对RH装置内钢液流场与脱碳过程进行了耦合计算;采用修正的均相流模型计算流场,避免了先前的一些不具推广性的方法,如简化计算区域或者预先规定含气率分布等.分别对有、无旋转磁场作用时的RH系统进行了模拟计算.模拟结果表明:流场和脱碳过程与现有文献中实验结果相符合;当旋转磁场作用后,磁感应强度为0.04 T时,初期脱碳速度比无旋流作用时增加了约15%,这是由于旋流增加了系统的搅拌能,提高了脱碳反应速率.脱碳反应进行到最后阶段,不同磁感应强度下的碳含量趋于同一稳定值.

A mathematical model was developed to investigate the molten steel flow and decarburization process in RH vacuum degasser system under the action of electromagnetic field. A modified homogeneous flow model was introduced to calculate the flow field in RH degasser, thus getting rid of some earlier methods that are unavailable to be generalized, such as reducing the computation region or presetting the distribution of gas volume fraction. The RH system with and without rotating magnetic field were simulated, and the numerical results showed that the flow field and decarburization process are in agreement with the experiment results in some earlier works. At the early stage of the decarburization reaction, when magnetic flux density is 0.04T the decarburization rate of RH system with electromagnetic stirring is 15% higher than that without electromagnetic stirring because the vortex due to the stirring enhances the stirring power hence the decarburization rate. Finally, the carbon contents under different magnetic flux densities tend to the same stable value.