Simulation Flow Heat Transfer And Inclusion Aggergation In Contininuous Casting Tundish

Continuous casting process is the last link in the steelmaking process,and it is also the last chance to control the cleanliness of the steel before solidification.In modern continuous casting production practice,tundish is not only a storage of liquid steel containers,but also a refining equipment for controlling composition,temperature and cleanliness of molten steel.The flow field and temperature field of molten steel in continuous casting tundish have important influence on the quality of billet.In this paper,the physical simulation of tundish for continuous casting is carried out.Different schemes physical simulation experiments are carried out to investigate the influence for whether or not with weir and dam,the location and angle of the hole on the weir and dam,and the turbulence is investigated.The results show that the best scheme is the scheme that the distance between the dam and the outlet is 329 mm,the front and side of the dam are opened holes,and the opening angle of the side hole is up to 8 degrees.In this scheme,the average dead zone ratio of the flow from 1 to 3 is about 9.5%,3.8% and 2.5%,and the average residence time of the flow from strand NO.1 to 3 is 1400.7 s,1191.9 s,and 1006.7 s.The mathematical model of flow,heat transfer and mass transfer of molten steel in continuous casting tundish was established by using commercial software Fluent,the influence of the boundary conditions of the retaining wall and inlet velocity on the convection field,temperature field and concentration field is further studied with the physical simulation experiment and the numerical simulation.The calculation results show that schemes which the front and side of the dam are opened holes is much better on the composition and temperature mixing,and the average residence time will be extended.The numerical results are in agreement with the physical simulation results.In this paper,a mathematical model for the collision and aggregation of non-metallic inclusions in molten steel was developed by using the user defined function(UDF)with Fluent as the platform.The Eulerian concentration field model is established by using the Smoluchowski equation as the source term,and the growth of inclusions in billet continuous casting tundish was simulated under the condition of two dimensions.The results show that,in the course of the collision with the turbulence as the core,the distribution of the concentration field is similar to the flow field.Using the equal volume ratio,the non-metallic inclusions in molten steel are grouped according to the volume,and the corresponding PSG model is employed in inclusion aggregation.It is feasible to calculate the inclusion aggregation in the molten steel.