Mathematical modelling of fluid flow and heat transfer in steel ladles

Abstract: In this thesis work, three mathematical models, each of which is suitable for simulating a particular process in the operation of steel ladles, have been developed. Firstly, by using a finite-difference mathematical method (FDM), a one-dimensional numerical model for calculating heat transfer through ladle wall, bottom and top slag layer was established. This FDM model was used to provide transient and structure dependent heat loss fluxes for further modelling of fluid flow and heat transfer in steel ladles. Then, with a computational fluid dynamics (CFD) mathematical approach, a two-dimensional CFD model for simulating fluid flow and heat transfer in steel ladles during the holding period before teeming was developed. With this model the natural convection and thermal stratification phenomena occurring in steel ladles were investigated. Further, the two-dimensional CFD model was finally extended into a three-dimensional CFD model to include simulations on the fluid flow and heat transfer in steel ladles with drainage during teeming, so that the interaction between natural convection and drainage flow was examined. By using this three-dimensional CFD model, it is possible to predict the steel stream temperature during teeming which is important for further prediction and control of steel temperature in tundishes during continuous casting.