Large eddy simulation of turbulent flow with the effects of DC magnetic field and vortex brake application in continuous casting

Abstract

Vortexing flow exists in the free surface of molten steel in the slab continuous casting process and leads to uncleanness of steel. A large eddy simulation (LES) model has been developed to simulate the vortexing flow phenomena with the effect of DC magnetic field and vortex brake application in the slab continuous casting process. The influence of the submerged entry nozzle (SEN) port angle and the SEN depth to the turbulent vortex was analyzed and the mechanism of the turbulent vortex and the biased vortex formation was found. The vortexing flow is the result of shearing of the two unsymmetric surface flows from the mold narrow faces when they meet adjacent to the SEN. The unsymmetric surface flow comes from the unsymmetric upward re-circulating flow, which is caused by turbulent energy of the fluid for turbulent vortex and caused by biased flow and the turbulent energy of fluid for biased vortex. The new vortex brake can eliminate the turbulent vortex and suppress the biased vortex significantly by removing the downward component of the vortexing flow. When the magnetic field is located at the free surface, the turbulent vortex and the biased vortex can be eliminated.