Mathematical Model and Plant Investigation to Characterize Effect of Casting Speed on Thermal and Solidification Behavior of an Industrial Slab Caster

Abstract

Development of a validated 3D transient mathematical model for modeling the fluid flow and solidifica- tion process in an industrial continuous slab caster has been demonstrated. The model couples thermo- fluid aspect of mold and sub-mold region by utilizing a standard Enthalpy-porosity method. Extensive plant level measurements of mold heat fluxes and thermocouples data, breakout shell thickness profile, and macrostructures were carried out to evaluate proper input of heat transfer and other conditions for the model. A suitable validation of the model is established with slab surface temperature and solidified shell thickness profile as measured from a breakout shell in the caster plant. An insight is drawn for an industrial slab caster from the model results analysis for a range of operating parameters of casting speed and SEN submergence depth as employed in the caster. Evolution of a solidified shell thickness profile is simulated. Slab surface temperature mapping is drawn from the model and discussed its variation originating due to fluid flow inside the solidified shell. Casting speed is shown to have a dominant effect as temperature rise of order of 50°C are observed as it is increased from an average plant value of 1.4 m/min to peak of 1.8 m/min. Similar effect is also reflected in the solidified shell thickness profile as shell thickness gets thinner by an order of 6 mm in the sub-mold region due to increase in casting speed from an average to peak value. The effect of SEN submergence depth is also outlined.