2004 Volume 44 Issue 8 Pages 1376-1383
The role of thermal-driven buoyancy flow in the steady macro-solidification process of a continuous slab caster and its effect on the predicted flow and temperature distribution are discussed by combining the non-dimensional analysis and the predicted results obtained from a steady three-dimensional coupled fluid flow, heat transfer and macro-solidification model. Results show that the relative strength among the thermal-driven buoyancy flow, the forced flow caused by the SEN impinging jet and the fluid flow through the porous matrix of mushy-zone continuously changes. The strength of thermal-driven buoyancy flow in the mold and sub-mold zone of slab caster is dependent on the characteristic flow velocity, temperature difference and the porosity-permeability ratio relation. The convection flow caused by thermal buoyancy at liquidus temperature of steel can result in the occurrence of local turbulence. The obvious effect zone of the thermal buoyancy flow on the predicted flow and temperature is in the region where the forced flow has become inferior and the mushy porous flow does not play a dominant role.