Dynamics of two-phase downwards flows in submerged entry nozzles and its influence on the two-phase flow in the mold

• Published in: International journal of multiphase flow 2005-05, Vol.31 (5), p.643-665
• Main Authors: Ramos-Banderas, A., Morales, R.D., Sánchez-Pérez, R., García-Demedices, L., Solorio-Diaz, G.
• Format: Article
• Language: English
• Subjects: Applied sciences; Bubbles; Continuous casting; Exact sciences and technology; Fluid dynamics; Fundamental areas of phenomenology (including applications); Gravity die casting and continuous casting; Iron and steel making; Metals. Metallurgy; Mold; Multiphase and particle-laden flows; Nonhomogeneous flows; Physics; PIV; Production of metals; SEN; Two-phase flows
• ISSN: 0301-9322; 1879-3533
• DOI: 10.1016/j.ijmultiphaseflow.2005.01.010

Gas–liquid flows inside the submerged entry nozzle (SEN) of a slab mold and its influence in the flow field in the mold were studied using video recording, mathematical simulations and particle image velocimetry (PIV) approaches. Bubbly and annular flows in the SEN yield structurally-uncoupled and structurally coupled flows in mold, respectively. High gas loads (ratio of mass flux of gas and mass flux of liquid) at high casting rates lead to increases of bubble population and bubbles sizes due to coalescence processes whose rate exceeds that of their breakup. The presence of gas bubbles or gas layers inside the SEN lead to periodical twisting of the liquid flow that induces biased flows through both ports yielding uneven flows in the mold. A multiphase mathematical model predicts acceptably well the flow dynamics of two-phase flows inside the SEN.