Non-Uniform Thermal Transfer of Molten Steel and Its Effect on Inclusion Particles Removal Behavior in Continuous Casting Tundish

Abstract

The temperature gradient inside a tundish leads to the uneven density distribution of molten steel, resulting in thermal buoyancy, which has a significant impact on the motion of inclusion particles. Based on practice data and necessary assumptions, a three-dimensional model of a tundish considering non-uniform thermal transfer was established. The flow and temperature distribution were studied, and the changes in inclusion removal rate were compared with different casting speeds and temperature reduction rates using computational fluid dynamics simulation. It was observed that, when the inlet temperature is higher, the molten steel floats up under the action of thermal buoyancy, which can form a horizontal stream behind the weir. While the inlet temperature is lower, the horizontal stream cannot be maintained, resulting in a decrease in the removal rate of inclusions. Increasing the casting speed will increase the velocity of the molten steel in the tundish, make it easier to shorten the temperature difference between the inlet and outlet, and reduce the removal rate of inclusions. When formulating production processes, the impact of thermal buoyancy on the flow field should be taken into account.