Mathematical Simulation Of Bubble Formation And Motion Processing And Inclusion Removal In Gas Curtain Tundish

In this paper, at first, the research histories and current development in the gas curtain technique of tundish was summarized and reviewed systemically. According to the practical production conditions, the factors affecting properties of the gas curtain brick were studied.Then the bubble force bearing was analysed according to the recent research of the bubble behavior in gas curtain brick and the brick's property parameters, and bubble formation mathematical model was established. MATLAB was used to simulate this process, and study the relation of the changing of bubble's diameter and the velocity of flowing metal, the density of flowing metal, the viscosity of flowing metal, the flux of gas, the diameter of air hole, the surface tension of the bubble and so on. Follow that VOF model was applied, bubble motion was studied.Finally, established a model of inclusion removing with bubble flotation, inclusion trajectories and removal in the gas curtain tundish were simulated using Lagrangian random particle tracking approach. The factors affecting particle moving and removal were analyzed and the mathematical model for calculating inclusion removal rate in the gas curtain tundish was more accurate.The results show that adopting oscillating casting and pressure oscillating technology, the porosity of the samples can be above 30% as well as the higher strengths, favorable permeability, uniform distribution small size pores can be acquired for the samples. Steel liquid velocity, gas flow rate and pore size are important factors to deside the bubble size. The gas curtain could not formate when gas flow rate is too small, and the bubble pathway is different as different gas flow rate or positions. The small size (diameter less than 50μm) are removal primarily by bubble flotation.So removal by bubble flotation could not be neglected.