Modeling of slag eye formation over a metal bath due to gas bubbling

When gas is bubbled through a molten metal, overlying slag is pushed to the side forming an open “eye” of exposed metal. Eye sizes were measured in room-temperature modeling over a wide range of conditions including the fluids to simulate slag and metal, gas flow rates, and depths of both fluids. A mechanistic model for eye size was developed from fundamental fluid flow considerations. The model expresses a dimensionless eye area in terms of a density ratio of the fluids and a Froude number. The model is consistent with the present experimental results and those of others in different liquid systems. Finally, previously published correlations for eye size have been critically evaluated.