3D CFD Model of Ladle Heat Transfer With Gas Injection

A fully transient 3D CFD model of an industrial argon bottom-stirred ladle with two eccentric porous plugs was developed. The computational domain included molten steel, slag, air and refractory phases. The slag-air interface was set as a free surface to ensure that the influence of the flow and the heat dissipation at the slag free surface on the temperature of the molten steel can be considered simultaneously. As a result, the model reasonably predicted the velocity and temperature distribution of molten steel, heat losses from the top slag layer and the temperature distribution in the refractory walls due to bottom gas injection. Previous numerical models on heat transfer in ladles have either neglected bottom gas injection, assumed a constant heat flux through the top slag layer or assumed a flat surface. The current mathematical model overcomes the previous limitations, it is capable to predict fluid flow and temperature distribution under transient conditions comparing a flat and a free surface. It is shown that the assumption of a flat surface leads to errors in the numerical predictions, it also predicts heat losses by the top slag surface and the refractory walls.