In a steel continuous casting mold, argon bubbles injected through the submerged entry nozzle undergo transport, coalescence, and turbulent breakup, producing a polydisperse bubble swarm that affects flow stability and defect formation. In this study, an Euler–Lagrange model coupled with bubble collision coalescence and turbulence-induced breakup sub-models was established and validated using water model observations. Three daughter-bubble volume distribution models were compared in terms of bubble-cloud morphology, number-fraction distribution, and median-diameter evolution at different gas flow rates. For the median bubble diameter at different gas flow rates, the M-type model gives the lowest mean absolute error of 0.0349 mm. Large bubbles with diameters greater than 2.5 mm accounted for about 4% of the total number and were mainly concentrated near the SEN, whereas small bubbles with diameters of 1.0–1.5 mm accounted for about 60% and were dispersed throughout the upper recirculation region. Mechanism analysis further shows that bubble transport is drag-dominated in the high-velocity jet region, while buoyancy becomes more important in weaker flow regions; turbulent breakup is localized mainly in high-dissipation regions.
Lai et al. (Tue,) studied this question.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: