Numerical analysis of the heat transfer behavior of steel stream in the converter tapping

Abstract

The present study investigated the flow dynamics and heat transfer behavior of molten steel during converter steel tapping. This research lays the groundwork for designing accurate post-furnace temperature models and enabling lower tapping temperatures. Considering the influence of slag and the Coriolis force on the process, a mathematical model was developed to characterize both the transient flow dynamics of molten steel within the converter and the heat dissipation of the steel stream in the air. Moreover, a physical model constructed based on similarity principles elucidated the impacts of standing time and the Coriolis force on the remaining steel volume in the converter at the moment of slag entrapment. Results showed that as standing time increased or tapping hole size decreased, the remaining steel volume in the converter decreased. When the Coriolis force was included, the percentage of remaining steel volume was lower compared to simulations without it. Numerical simulations precisely determined the trajectory of the steel stream in the air domain, facilitating improved coordination between the converter and the ladle. Furthermore, at a tapping temperature of 1700°C and a tapping hole size of 140 mm, heat loss of the steel stream in the air domain led to a temperature decrease of 1.02°C. Heat loss decreased with increasing hole size. Lowering the tapping temperature by 50°C could reduce the temperature decrease from the air domain by 0.1°C. Finally, the study proposes preliminary strategies for lowering tapping temperature.