SWIRLING EFFECT IN IMMERSION NOZZLE ON FLOW AND HEAT-TRANSPORT IN BILLET CONTINUOUS-CASTING MOLD

A numerical analysis and water model study of the mold region of a con tinuous casting apparatus are performed with a novel injection concept using swirling flow in the pouring tube, to control the heat and mass transfer in the continuous casting mold. As a result, the following r esults were found: (1) By changing swirl strength, it is easy to contr ol the flow pattern as well as the direction of the flow. (2) Uniform velocity distribution can be obtained within a very short distance fro m the outlet of the nozzle. (3) Heat and mass transfer near the menisc us can be remarkably activated compared with a conventional straight t ype immersion nozzle without swirl. (4) Swirl helps the superheat in t he melt dissipate. (5) Penetration depth of nozzle outlet flow is decr eased remarkably by the application of swirling. Those findings mentio ned above are very useful to control the flow pattern in the billet an d bloom continuous casters.