Simulation of the Filling of a Liquid Steel Sampler

摘要

Steel samples extracted from the ladle furnace in liquid state are vital to monitor the steel making process in the iron & steel industries. The main function of the steel sample is to exam whether the steel is at the aimed composition for elements that dissolve in steel. In addition, more interest is arising to determine the inclusion characteristics in steel samples, in order to monitor the development throughout the process. However, the molten steel sampling is a process involving multi-phenomena such as a high temperature, a fast solidification, reoxidation of steel and a highly turbulent flow pattern. Therefore, mathematical simulations have been carried out to fundamentally study the sampler filling process. The Wilcox k-ω turbulence model was employed to predict the turbulent flow. The calculated results show that flow patterns inside the sampler can be classified into three distinct flow regions: the vortex flow region close to the free surface, the lower horizontal flow region and the middle vertical flow region. From the flow and turbulence data, the inclusion particle collision volume rate was calculated to study the influence of turbulent flow on the inclusion growth in the sampler during fillings. It is shown that the collision volume in the sampler is much higher than that found in the ladle furnace, where the steel sampling normally takes place. This is due to the high turbulence energy dissipation rate in the samplers compared to the ladles.