Numerical Simulation Of The Electromagnetic Brake Process In The Mold Of CSP Thin Slab Continuous Casting

In this paper, the numerical simulation is adopted to study the influences of electromagnetic brake(EMBr) on the flow and heat transfer behavior of molten steel for the funnel type mold which is used in CSP continuous casting process under different the submerged entry nozzle (SEN) structure. Firstly, the phenomenon of fluid flow and heat transfer in the CSP funnel type mold are simulated with the aid of computational fluid dynamics software FLUENT, and the influences of different SEN structure on the flow field and temperature field are observed. Secondly, the distribution characteristics of magnetic field are calculated by using the finite element software ANSYS and the relationship between magnetomotive force and the magnetic field distribution are studied. Finally, the magnetic field data which were calculated by ANSYS are imported into the FLUENT, through coupling magnetic field with flow field, temperature field and solidification field, the influence of EMBr on the distribution of flow field, temperature field and solidification of molten steel in the CSP mold by the SEN with four ports is simulated.The simulation results show that:the distributions of flow field and temperature field in the CSP mold are improved after electromagnetic brake technology is used in it, which also can improve the quality of thin slab. Compared with the traditional SEN with two poets, the SEN with four ports is more suitable for the thin slab continuous casting process of CSP, because the parameters of the mold with the SEN with four ports are superior to the parameters with the two side hole immersed SEN (In the same conditions, compared with the two side hole immersed SEN, the end of steel mainstream discharging from the SEN with four ports goes farther from the narrow face,meanwhile, the temperature of surface is bigger).The results show that, for mold with the SEN with four ports, the bigger magnetomotive force is, the more obvious the influence of EMBr on center plane shows, which does not mean the effect of EMB is the best. The casting speed has a complicated relationship with the effect of magnetomotive force in mold:with magnetomotive force keep in constant, each0.5m/min the casting speed increases,the flow speed of the surface in mold will be0.02m/s bigger. Therefore, to obtain a better effect of EMBr, the magnetomotive force should be increased or decreased in5000a·n accordingly for each0.5m/min the pull speed of slab increases or decreases. The submerged depth of SEN below the meniscus has a complicated relationship with the effect of magnetomotive force in mold:with magnetomotive force keep in constant. the influence of EMBr is the most obvious when most of the mainstream distribution in the main magnetic field region. In the other conditions remain unchanged, with the increase of the submerged depth of SEN, the flow speed of the surface in mold drop.