Improvement in secondary cooling of continuous casting of round billets through analysis of heat flux distribution

Abstract

A mathematical model of heat transfer and solidification for a continuous casting of round billets was developed. The water flux density of the secondary cooling zone was experimentally measured, using an apparatus in industrial scale with two types of nozzles, flat jet and full cone jet. The profiles of water distribution were applied on the mathematical model. The results showed that the water distribution is not uniform in both longitudinal and angular directions owing to the unevenness of the spray and to the curvature effect of the round billet. This non-uniformity causes important variation of the heat transfer coefficients and superficial temperature of the billet, especially in the first cooling zones, where the temperature is higher. The mathematical model was used to simulate a change of nozzle type in the first cooling zone. The results showed that the heat flux and superficial temperature variations were reduced with a full cone jet nozzle in comparison with the flat jet nozzles.

Keywords:

• Water flux distribution
• Heat transfer coefficient
• Secondary cooling
• Round billet
• Mathematical model

Acknowledgements

The financial support of Fundação de Amparo à Pesquisa do Estado de Minas Gerais (FAPEMIG), Brazil, in the form of a research grant to R. Tavares, process no. TEC-APQ-00373-11, is gratefully acknowledged. The authors also acknowledge the financial support of CAPES to the graduate program.