Effects of Cooling Water Supply Nozzle Array on Cooling Performance of Run Out Table in Hot Rolling Process

摘要

Intricate physical phenomena such as boiling heat transfer, free surface flow, and the moving of a cooling object (running hot plate) are included in the ROT (Run Out Table) cooling process of hot rolling. Mixed reciprocal actions are also included. Therefore, analyzing the process with considering all relevant phenomena simultaneously has been an important objective in this field for a long time. In the ROT process, cooling performance could be affected by the upstream process, and by various environmental factors such as refining, reheating, and the ambient temperature and humidity. In this study, with such disturbances numerically fixed, cooling capacities are compared by varying the arrangement of the cooling water supply nozzle. Generally, the cooling heat flux is known to vary in the plate running direction. Thus, clustering the nozzle in the upstream or downstream direction could affect the average cooling capacity of the facilities. The cooling histories, the heat fluxes on the plate surface, and the thickness of the Leidenfrost steam layer are compared for various nozzle arrangements.