Numerical Simulation Of Fluid Flow And Related Phenomena In Thin Slab Continuous Casting

To improve the efficiency in the process of continuous casting and the quality of its products, which is of great significance to further reduce energy consumption and environmental pollution, at the same time, it can improve labor productivity and has significant social benefits. Using mathematical modeling method to investigate the phenomena in casting process has many adbantages, so this disertation mainly investigated fluid flow and related phenomena in the thin slab casters.Researchers usually use single phase model to analyze the turbulent fluid flow in the mould of continuous casting, which ignores the tranport phenomena during the interface at the meniscus and use the potential energy to evaluate the height of meniscus fluctuation. In this paper, a two-phase model is developed to describe the turbulent fluid flow and the transactions phenomena between steel-slag interface in the CSP funnel-type mould. The results show that, with the increase of cast speed, the meniscus fluctuation and the molten steel jet from sunmerged entry nozzle will become more serious.Slab size can strongly affect the mould metallurgical behavior. In this paper, the effect of slab size on mould metallurgical behavior of CSP funnel-type mould and FTSC H2mould was discussed. With increase of the slab size, the location of vortices both in the CSP and FTSC mould lower down and the recirculation zones become longer. The level fluctuation at the meniscus region becomes more serious and the shell thickness at the mould exit becomes thicker. In the CSP funnel-type mould, with the increase of slab width, the effect of EMBr will become insignificant.The transient stages during continuous casting are inevitable. Minimizing the negative effects at the transient casting stage is still a great challenge to researchers. To save the steel and lower costs, it is necessary to control the steel cleanliness at the transient stages. In this paper, a three-dimensional mathematical model was to study the transient molten steel flow phenomena in a CSP caster with EMBr during the casting start period. An algorithm of VOF has been employed to simulate the air/steel interface. Use dynamic mesh to control the movement of dummy bar. The results indicated that there a serious entrainment of air during the filling process and a large fluctuation in the top surface level at the beginning of dummy bar moving. At the cast start process with dummy bar moving, when the meniscus is stable, there still exists flow deviation of molten steel in the funnel-type mould. EMBr can significantly restrain the turbulent flow of molten steel and the fluctuation at the time of the dummy bar moving. When the free surface has its stabilization, the EMBr can provide a positive effect to reduce the flow deviation of molten steel in the funnel-type mould.