Unsteady Pressure Coefficient around an Elliptic Immersion Nozzle

摘要

An unsteady molten steel meniscus flow sometimes occurs in the continuous casting mold. When it impinges on the immersion nozzle, a severe vertical pressure difference is induced on the outer surface of the nozzle. Mold powder entrapment near the immersion nozzle is closely associated with the pressure difference. The use of an elliptic immersion nozzle is expected to effectively lower the difference, and accordingly, suppress the mold powder entrapment. The pressure difference around the elliptic immersion nozzle however is not quantitatively known yet. In this study it was numerically calculated by the vortex method over a wide aspect ratio range of the nozzle for two types of unsteady meniscus flows. The validity of the numerical results was confirmed from a comparison with previous results obtained from cold model experiments.