Study on Influencing Factors and Their Combined Effects on Multiphase Behavior in Tundish Pouring Zone

The tundish pouring zone involves relatively intense multiphase turbulence and is vulnerable to melt contamination from air and slag. Both numerical and hydraulic models were constructed to investigate the multiphase flow characteristics inside the pouring zone of a single-strand tundish, in consideration of ladle shroud, argon flow rate, casting speed, slag thickness, turbulence inhibitor (TI), and their combination. The fundamental gas–liquid flow patterns were discussed in the tundish pouring zone under different flow control devices. It was found that the average feret’s diameter of bubbles at the trumpet-shaped ladle shroud (TLS) outlet is approximately 38.9 pct larger than that of the conventional ladle shroud (CLS), due to lower bubble velocity and sudden velocity decrease in the TLS, which facilitates bubble coalescence and growth. The increase in argon flow rate results in the expansion of the tundish open eye (TOE), and a correlation has been derived between TOE area and argon flow rate under different slag thicknesses. The TLS also brings about lower bubble velocities and is beneficial in reducing the TOE. The combination of a TI and CLS intensifies the upward plume flow and adversely enlarges the TOE, while the combination of a TI and TLS shows minimal effect on the TOE due to different flow patterns. Additionally, the higher casting speed shows less effect on the change of TOE due to the limited plume flow height.