Simulation And Experiment Of Flow And Thermal Conduction Laws In Molten Steel Pool Of Twin-roll Casting

As an international frontier technology, the twin-roll strip casting process has a very large potential power in market competition. But so far, most of the thin strips produced by this casting process have a variety of defects. The structure of flow distribution device and the process parameters determine the flow and thermal conduction pattern in the molten pool. The study on flow and thermal conduction of molten steel in twin-roll pool has a very important theoretical and practical significance.This paper takes the molten pool as research object constructed by twin-roll, side dam and wedge-shaped device. Taking roll rotation into consideration, the mathematical model of flow and solidification is established with the entire casting pool as a two-phase free surface flow of air and molten. In this case, the effects of the structure of wedge-shaped device and casting process parameters on molten steel flow pattern, temperature ditribution on pool surface and the slab temperature distribution are analyzed.The research results show that the temperature of molten steel in the longitudinal symmetry plane distributes in the approximation cosine pattern bsed on the inlet location. When the nozzle angle is between 0°and 33°, the temperature difference is relatively small in the longitudinal direction of casting strip, so, the temperature distribution is relatively even. The surface temperature of molten pool increases with increasing of nozzle height, while the slab temperature is reduced. In addition, the temperature of free surface and outlets are both increased with the increasing of casting speed pool and superheat temperature. In the actual casting process, the solidification rate of molten steel will be controlled and level surface crusts will be avoided by the rational operating of casting process parameters according to the results. So, the casting defects will be reduced largely. Meanwhile, the results provide a theoretical basis for designing a reasonable flow distribution system in two-roll strip casting.