ABSTRACT The non‐steady working state of the tundish, caused by the ladle changeover process, represents a weak link in continuous casting production. This study develops a hydraulic simulation system with adjustable flow rates and controllable liquid levels, using particle image velocimetry (PIV) velocity measurement to quantitatively assess the flow characteristics of the tundish during non‐steady‐state flow processes. The research findings reveal that the decrease and subsequent rise in the liquid level during ladle changeover and casting startup are accompanied by significant changes in the flow state within the tundish. After the ladle change, the liquid level drops, and the molten steel flow velocity decreases gradually. Compared to the steady working state, when the liquid level drops to 425 mm, the average velocity in the casting zone decreases by 27.47%. The slow flow of molten steel can lead to excessive temperature drops, adversely affecting the quality of the cast slab. Conversely, after casting startup, when the liquid level rises to 475 mm, the average velocity in the casting zone increases by 346.29%. Such high flow velocities of molten steel may cause slag entrainment and secondary oxidation. Meanwhile, the optimized tundish structure designed for steady‐state casting conditions remains effective during actual non‐steady‐state operations. When the liquid level drops, the average velocity in a tundish equipped with an L‐shaped weir decreases by 14.71%, and when the liquid level rises, the average velocity increases by 90.33%. The flow field velocity distribution and rate differences in this configuration are smaller than those observed in a tundish without flow control devices.
Zhou et al. (Wed,) studied this question.