Study On Optimization Of Two-Strand T-Type Tundish Configuration In Continuous Casting

The fluid flow in a two-strand T type tundish was studied and optimized with physical and numerical simulation in this research, and an optimum tundish configuration was obtained. A two-strand T type tundish model was set up in laboratory with1:2.5scale from the two-strand T type tundish prototype. Modeling experiments were carried out under the condition in which Froude number was kept to be equal. The mathematical model describing the flow phenomena in the tundish was established from the continuity equation, momentum equation, k-s turbulent kinetic energy model and energy equation. The FLUENT commercial software is used to numerically calculate the flow and temperature fields in different tundish configurations.The physical simulation experiment results indicate that in former tundish configuration the minimum residence time, the peak time and average residence time are small and the dead volume proportion is large. The minimum residence time is35seconds, the peak time is about103seconds, the average residence time is273seconds, the active region proportion is about17.8%, and the dead volume proportion is29.5%. By comparing the tundish configuration10with the former tundish configuration, the minimum residence time is increased by251%, the peak time is increased by92%, average residence time is increased by26%, the plug flow volume proportion is increased by133%, and the dead volume proportion is decreased by61%, respectively. Flow characteristics of fluid in the tundish are improved greatly with the flow control devices of a turbulence inhibitor, a weir and two dams which have been optimized.By means of analysing the flow field of symmetry plain, free surface, longitudinal section through nozzle and longitudinal section at100mm position inside from nozzle, the molten steel generate a high-speed flow at the free surface of the former tundish and form a large circuit flow area close to the free surface after it flows out from the baffle holes. The flowing condition in the optimal tundish configuration has been much improved, compared with the former one. In the optimum tundish configuration, molten steel can flows properly, the free surface keeps steady and streamline of molten steel is longer than the former case. So the molten steel has enough residence time in the optimal tundish configuration, which is of great benefit to the removal of the non-metallic inclusions.By means of analysing the temperature field of the whole tundish, free surface and vertical section through nozzle, the temperature has a great difference between the impact area and casting area in the former tundish configuration, and there is a large low temperature area in the center zone of the tundish. The temperature in the optimal tundish configurations decreases gradually along the flow direction of molten steel. The temperature distribution in the optimal tundish is more reasonable.