Evaluation of submerged entry nozzle performance in slab continuous casting molds with different cross sections

This study examines the behavior of fluid flow, heat transfer, slag entrainment, and solidification within slab continuous casting molds featuring two distinct cross-sectional geometries. A combination of physical modeling and numerical simulation was utilized to assess the performance of the submerged entry nozzle (SEN) in these molds. The findings reveal that increasing the SEN immersion depth ( D ) significantly mitigated surface level fluctuations at one-quarter of the mold width, with the 250 × 1550 mm 2 cross-section demonstrating superior control compared to the 250 × 2000 mm 2 counterpart. However, it was found that oil entrainment was more likely to occur when the D value of the SEN was set at 120 mm and 140 mm. Conversely, depths of 160 mm and 180 mm resulted in a more stable water-oil interface. Additionally, increasing the value of D led to a reduction in temperature uniformity across the surface of the mold. The accuracy of simulated shell thickness was confirmed by comparison with empirical formula predictions. Increasing the value of D from 120 mm to 180 mm led to a reduction in shell thickness by 2.2 mm for the 250 × 2000 mm 2 cross-section and 0.4 mm for the 250 × 1550 mm 2 cross-section at the mold outlet. These results suggest that the current SEN design is appropriate for use in slab continuous casting with both cross sections. It is recommended that the SEN immersion depth is maintained between 140 mm and 160 mm for optimal performance.