两段式无缝软接触电磁连铸结晶器内的电磁场分布

ELECTROMAGNETIC FIELD DISTRIBUTION IN TWOSTAGE SLITLESS MOLD FOR SOFT CONTACT ELECTROMAGNETIC CONTINUOUS CASTING

通过有限元数值模拟,研究了两段式结晶器上半段长度、感应线圈的位置及液面位置对结晶器内部磁场的影响,分析了两段式结晶器的电磁场分布规律.结果表明:两段式结晶器的上半段越长或线圈位置越靠上,结晶器的透磁效果越好;液面位于线圈中心偏上20 mm时,内部磁场的作用效果最佳.在本研究条件下,两段式结晶器的透磁效果良好,磁感应强度主要集中在结晶器上半段钢液的弯月面区域.纵向磁场在结晶器上半段高度的范围内逐渐增强,在结晶器下半段高度的范围迅速衰减;周向磁场在钢液表面均匀分布;径向磁场由钢液表面向内部逐渐衰减.与切缝式结晶器比较,两段式结晶器内部磁场分布更均匀.

Length of the top half of mold, coil location and meniscus level in the two-stage soft contact slitless mold were analyzed through 3-D FEM numerical simulation method. The distribution of electromagnetic field in the whole mold system was also studied. Magnetic flux density in mold increased with the length of the top half of mold increasing. Coil should be placed near the top of mold to increase the magnetic field. Initial meniscus level should be controlled between the center and the top of coil to obtain the ideal soft contact effect. The alternating magnetic field can penetrate mold wall then impose on metal strand under the given conditions in this research. Magnetic field on vertical direction mainly acts on metal strand meniscus＇ location. The magnetic flux density increases in the top half of mold, but decreases greatly in the down half of mold. The magnetic flux density is uniform along circumferential direction but is degenerated along radical direction. The magnetic field in the two-stage mold is more uniform than that in the slit mold.