Article ID: ISIJINT-2018-832
The bubbles generated by argon blowing in a nozzle have important effects on the flow and heat transfer behavior of mold slag. To determine the effect of argon blowing on the flow and heat transfer behavior of liquid slag in the mold, we developed three-dimensional mathematical models coupled the volume of fluid and discrete phase models. The results showed a small circulation flow of liquid mold slag occurred near the nozzle side face and the mold narrow face respectively at the center plane between the mold wide faces. Additionally, we identified a larger circulation of liquid mold slag in the middle region of the mold. With increased argon flow rate, the flow velocity peak at the liquid steel and slag interface decreased, the temperature of the liquid mold slag increased. A moderate flow rate of argon improved the uniformity of flow velocity and temperature distribution of liquid slag and reduced the flow velocity peak at the interface of the liquid steel and slag. To avoid the solidification of liquid steel at the steel-slag interface near the mold face, moderately high casting speed and argon flow rate and larger inclination angle and immersion depth of the submerged entry nozzle may be beneficial. These results provide a theoretical basis to optimize the parameters of the argon blowing process and improve slab quality.