Flow control with local electromagnetic braking in continuous casting of steel slabs

A computational fluid flow model is applied to investigate the effects of varying submerged entry nozzle (SEN) submergence depth and electromagnetic brake (EMBr) field strength on flow in the mold cavity. The three-dimensional, steady K-epsilon model of the nozzle and liquid cavity in the mold used the magnetic induction method in FLUENT to incorporate the localized-type static EMBr field measured at a steel plant. The model was validated by comparing results with an analytical solution and with nail board and oscillation mark measurements collected at the plant. Increasing EMBr strength at a constant SEN depth is found to cause a deeper jet impingement, weaker upper recirculation zone and meniscus velocity, and a smaller meniscus wave. Increasing SEN depth without EMBr caused the same trends. Increasing SEN depth at a constant EMBr strength brought about the opposite: higher meniscus velocity, larger meniscus wave, and deeper penetration depth. Using the knowledge gained from this model, electromagnetic forces can be controlled to stabilize the fluid flow in the mold cavity and thereby minimize casting defects.