Physical And Mathematical Simulation On The Tundish And Mould For 4-Strand Bloom Continuous Caster In Panzhihua Steel

With the development of continuous casting process of high efficiency, the metallurgical effects of tundish and mould become more and more obvious. It is the key to process running smoothly and improvement of strand quality to thoroughly know and control the behaviors of molten steel in tundish and mould.The tundish and mould of a four-strand bloom continuous caster in Panzhihua Steel are the objects for investigation in the dissertation. The size of bloom cross-section is 360×450mm². The extent of drawing speed is 0.6-1.0m · min^-1. According to similitude principle, a 1:4 tundish model and a 0.6:1 mould model are established. Physical hydraulics modeling and mathematical simulation with commercial software "FLUENT" are both used to study the behaviors of molten steel in the tundish under three conditions: without flow control devices, "V type baffle and dams" cases and "turbo-stopper and dams" cases. The flow characteristics (residence time distribution, velocity flied distribution and flow visualization et al.), temperature characteristics, and the inclusion behavior in the tundish are mainly studied. And the same methods are used to study the flow characteristics (velocity field distribution, surface fluctuation, impacting pressure and impacting depth et al.), temperature field distribution and the state of flux in the tundish when straight channel or multi-hole nozzles (two-hole and four-hole) are used. In addition, the simulation on gas blowing into the mould and the investigation on the effect of optimized results in Panzhihua Steel have been done and described in the dissertation.Some conclusions can be drawn according to the study on the tundish. When no flow control devices are equipped, obvious short-circuited flow and large dead region exist in the tundish, the flow and temperature field are not uniform and the inclusions are difficult to be removed. When "V type baffle and dams" case 1 is used, the average residence time of molten steel can be prolong marvelously , the dead region decreases , the piston flow region increases, the inclusions are easy to be removed and the flow and temperature filed are more uniformly distributed. The "turbo-stopper and dams" cases cannot efficiently improve the behaviors of molten steel in the tundish. The spontaneous diffusion of tracer can lead a little warp to the measure of residence time. The operation parameters are also obtained by experiments.The study on the mould shows that straight channel nozzle Z2^#, two-hole nozzle 2^#...