Simulation of the flow-heat transfer process in billet mold and analysis of the billet rhomboidity phenomenon

Abstract

To investigate the influence of inlet temperature and velocity of mold cooling water on the heat transfer effects in a continuous casting mold, a three-dimensional fluid flow and heat transfer coupled model was established, containing steel, copper tube and cooling water zone. Using Fluent, this model simulated the flow and heat transfer of liquid steel and cooling water, solidified shell growth, and heat transfer through air gap and mold fluxes. Furthermore, the accuracy of the model was verified by comparing the shell thickness and temperature fields in this study with those from other studies. The model results suggested that the inlet water temperature notably affects the temperatures of the mold cold surface. If the inlet water temperature exceeded 313 K, the highest temperature of the cold surface surpassed the boiling point of water, which could be a reason for billet rhomboidity. An increase of 0.49 m∙s−1 in water velocity diminished the adverse effects of an increase of 4 K in inlet water temperature. Off-squareness can be prevented in the actual production process by following this method.