HIDRODINÁMICA DEL ACERO LÍQUIDO DURANTE EL LLENADO DE LA OLLA.

Abstract

The computational approach of this model involves the solution of Navier-Stokes Equations for a multiphase flow through an explicit method using the Volume of Fluid (VOF) model in order to define sharp interfaces, among air and liquid steel. A multiphase numerical analysis focused on flow dynamics and particle trajectories during steel tapping operations was developed. The three-dimensional (3-D), multiphase and unsteady turbulent fluid flow model of steel tapping operations was simulated through the solution of a set of continuity equations, one for each phase, and a set of momentum transfer equations for all phases and the standard k-ε two-equation turbulence model as is explained below. The minimum residence times (MRT) refers to those minimum times that a particle remains in the metal bulk before it emerges to the bath surface. The numerical results indicate that the MRT for lighter additions than steel (ferrosilicon and aluminum) are independent from bath level, fall height and flow dynamics of the melt. Neutral buoyant additions (Fe-Mn) are strongly dependent on fluid dynamics of the melt and bath height. Denser additions (like Fe-Nb) yields long residence time inside the melt before first emerging to the bath surface. However, when this ferroalloy is added at high bath levels, close to the end of tapping, the particles remain in the corner formed by the bottom and the wall of the ladle during long times prolonging their melting rates.