(1281) Investigation of steel flow and non-metallic inclusions separation in a six-strand cc tundish

摘要

The tundish is a very important unit in continuous casting process. The flow of the liquid steel in tundish has a crucial influence on non-metallic inclusions separation. In order to improve separation rate of inclusions from liquid steel, investigations are being made worldwide to obtain the most favourable shape of the tundish working space by installing different flow control devices FCD (i.e. dams, weirs, turbulence inhibitors or gas curtains). The article presents computational studies of non-metallic inclusions separation in a six-strand industrial tundish during steady-state casting. Determination of size distribution of micro inclusions in steel have been performed with samples taken directly from continuously cast billets. Numerical simulations of the three-dimensional turbulent steel flow in the tundish are performed with commercial CFD code Fluent. With the calculated flow field, inclusion separation due to flotation to the covering slag is investigated. Non-metallic inclusions identified in the continuous casting billets during industrial experiments are used to evaluate the propriety of the numerical simulations in prediction of inclusion separation rate. For the inclusion separation at the steel-slag interface a standard and then modified boundary conditions are implemented. The influence of a turbulence inhibitor installed in the tundish working space on inclusion separation rate is mathematically investigated using a modified boundary condition validated previously with the water model experimental results.