Numerical analysis on transient thermal flow of the blast furnace hearth in tapping process through CFD

This paper aims to numerically simulate transient thermal flow due to sudden starting drainage of liquid iron from the blast furnace hearth with a sitting dead-man (coke packed structure) by solving the three-dimensional Reynolds averaged Navier-Stokes equation coupled with the transport equation of energy. With the effect of conjugate heat transfer, a computational fluid dynamic (CFD) was performed to generate the dynamic flow field and temperature distribution as function of time, evaluating shear stress on the wall in the hearth and heat flux in the refractories, respectively, during unsteady tapping process from a free convection as the initial stage (t = 0) to the turbulent mixed thermal flow as the final stage (t → ∞). It was found that the shear stress on the wall near the tape-hole is significantly raised with increasing tapping time, which corresponds to decrease temperature of the refractory around the tap-hole with tapping time shapely, when the liquid iron begins to flow out from the blast hearth. The obtained results can be used to optimize operating condition for a long campaigning life of blast furnace.