Simulation Study On Optimization Of The Structure And Bottom Gas Blowing Of Slab Continuous Casting Tundish

Metallurgy in tundish is an important step in the continuous casting process. Flow control devices in the tundish could be beneficial to equalize component and temperature of the molten steel and improve the flow state and to urge the inclusion removal through floatation and adherence.The original condition(Programme t00) is bad for the removal inclusions ,which has larger volume fraction of dead zone, smaller volume fraction of piston zone and larger critical removal diameter. So the ratio of 3:1 between the prototype and model of the tundish water model is established according to the similar principle, and optimization experiment is carried out. The programme is determined through the orthogonal test. According to assaying the RTD curves, two index values are gotten, which are the volume fraction of dead zone and volume fraction of piston zone of each programmes. The optimum condition is found in the presence of these two index value and comprehensive score system. And the result of the optimum condition is validated.According to the physical simulation and numerical simulation study on optimization of the structure, the following conclusions show: the optimum condition is height of weir 135 mm , depth of dam 90 mm , ditance between weir and dam 155 mm and distance between dam and long nozzle 195 mm . The average resident time is 341.39s, the volume fraction of dead zone decreased to 16.12%, the volume fraction of piston zone increased to 17.13%, the comprehensive score increased to 91.01 and and the critical removal diameter of inclusions is 74.8μm of this condition, which are improved.At the same time according to the study of exploring the bottom gas blowing of tundish, the following conclusions show: the optimum condition is flux of gas 450L/h, depth of dam 110 mm , ditance between weir and dam 235 mm and distance between dam and long nozzle 195 mm . The average resident time is 360.32s, the volume fraction of dead zone decreased to 11.47%, the volume fraction of piston zone increased to 21.95%, the comprehensive score increased to 100.48.Compared each index values between the optimization of the structure and the bottom gas blowing of tundish, the following conclusions show: the metallurgy effect of the bottom gas blowing of tundish is better than that of the optimization of the structure.