Numerical Simulation of the Optimal Flow for Inclusion Removal in Tundish
|School||Wuhan University of Science and Technology|
|Keywords||Continuous tundish Field synergy principle Temperature Field Inclusion Numerical simulation|
The tundishs are used for transition devices when molten steel flows from ladles to Mold for Slab, and they are very important in producting clean steel. In recent 30 years, the domestic and international metallurgists mainly study the tundish metallurgical functions with numerical simulation and physical simulation experiments. Lacking of theoretical guidance, the optimization design of tundish configuration cost high but low efficiency, because a lot of human and material resources are needed to put into the optimization. In this subject, the field synergy principle of optimization design for heat transfer exchanger has been successfully used to analyze the metallurgy transmission process. Not only the numerical simulation was completed for a single-strand tundish but also the applications that field synergy principle of optimization design were discussed. The main research contents are as follows:(1) The mass transport process in tundish has been analysed by the field synergy theory, and we can draw the conclusion that the removing of inclusion not only relate with stokes buoyancy and the steel flow but also depend on the synergy relationship between the flow field and and concentration distribution of inclusion.(2) The flow fields, temperature distributions and the synergy angles between the flow and temperature gradient in the one-strand tundish established with different flow controls were numerically calculated. The results show that: setting devices could reduce synergy degree between the flow field and the temperature gradient field in tundish, and the heat dissipation value increases, the temperature of the liquid steel uniformly distributed.(3) The flow fields, the inclusion which size range from 10~150μm concentration distribution and the synergy between the velocity vectors and the inclusion concentration gradients has been calculated in the tundish with different flow controls; The synergy relationship between the flow field and concentration distribution of inclusions has been discussed; And the the influence factors of removal inclusions has been analysed. The results show that the large particle size inclusions are removed mainly by stokes floatation and turbulence collision but we cannot draw the same conclusion in small size. The optimal scheme for an uniform temperature distribution and a largest rate of removing inclusions is scheme which is established with the devices dams and tubluence controller, and the result is consistent with the analysis of The field synergy principle.The study shows that the field synergy principle can be used to optimize the flow field in tundish. As a result, an uniform temperature distribution was get and the removal of inclusions was improved.