Theoretical study on gas flow and heat and mass transfer in a converter

A theoretical study was compared with a hot model experiment in order to understand gas flow and heat and mass transfer in a converter with a top blowing lance. The experiment was made in a 200 kg high frequency induction furnace equipped with an oxygen lance. Post combustion ratio, γ, measured by a mass spectrometer, increases with increase in lance height and decrease in oxygen flow rate. Transfer efficiency of reaction heat of CO and CO₂ formation to the metal bath decreases with increasing γ. Two-dimensional equations of continuity, conservation for momentum, enthalpy and gas species were solved numerically under the condition that the reaction rate at a fire spot is controlled by diffusion in a gas phase. The ad hoc model was used for the calculation of effective viscosity. The maximum temperature and CO₂ concentration are in the recirculating flow zone located between the lance tip and the depressed surface.