Multiphase flow inside a four-strand continuous casting tundish using three types of ladle shrouds

Numerical and physical models have been built and validated to study the multiphase flow inside three ladle shrouds and a four-strand tundish. A conventional straight ladle shroud and two types of trumpet-shaped ladle shroud (TLS) have been comparatively investigated. The maximum velocity at ladle shroud outlet reduces from 1.3 to 0.5 m/s, which indicates a quieter tundish pool. It is demonstrated that the use of a TLS can also decrease the maximum surface velocity from 0.16 to 0.13 m/s, which reduces the tendency of forming tundish open eye. The flow pattern and mixing behavior are improved inside the tundish, especially in enlarging the plug volume from 6.61% to 9.04%. The difference between the near and far outlets is narrowed when the TLS is applied. A computational program was developed to calculate characteristic parameters of different ladle shroud designs, and a dimensionless index was proposed to evaluate their mass and inner volume. Plant trials have been carried out, and the results showed that TLS can reduce level fluctuation in the pouring zone, which is beneficial to promoting better protective performance from secondary contamination and heat loss during continuous casting.