CFD Modeling of Solid Inclusion Motion and Separation from Liquid Steel to Molten Slag

A model of computational fluid dynamics (CFD) coupled with phase-field and flow-solid interaction (FSI) was built to simulate a solid inclusion’s floating in steel and interacting with the steel-slag interface. The numerical model was validated by a water model experiment. The effects of inclusion size, density and contact angle with the interface on the dynamic process and static position were investigated. The simulation results indicate that floating small size inclusions satisfy Stokes flow while a large size inclusion is with turbulent flow. When approaching the interface, the inclusion will decelerate in advance due to steel film drainage and there will be an acceleration of inclusion once the film ruptures. The static position of inclusion settling at the interface is related to the size, density and contact angle of inclusion, and among all these properties, the contact angle of the steel-slag interface with the inclusion is the dominant factor.