Investigation on Heat Transfer in Molds with Different Water-Cooling Structures Under Billet High-Speed Continuous Casting

The excellent water-cooling structure contributes to achieve efficient and reasonable heat transfer in mold, which is indispensable to realize billet high-speed continuous casting. Therefore, five kinds of unconventional cooling structures were designed, and the corresponding three-dimensional molten steel-mold-cooling water models coupled with flow, heat transfer, and solidification were established based on them. Then, the accuracy of models was verified by comparing heat flux with other studies. Finally, the temperature distribution characteristics in models under high casting speed were analyzed mainly, and the optimal water-cooling structure was proposed. The results show that high casting speed is beneficial to uniform the temperature of the strand, but will greatly reduce its thickness. Compared with other structures, the composite structure consisting of water seam and water channel has the best cooling effect. By using this water-cooling structure, the maximum hot face temperature of copper tube will reduce to 469 K and make mold temperature distribution more uniform at 6.5 m min(-1). Meanwhile, it can take away 5.58 pct more heat than conventional water seam in the process of molten steel passing through mold. Therefore, mold with water seam and water channel can further improve the production efficiency on the premise of ensuring the quality of the strand.