Numerical simulation of the cooling-down of high-zirconia fused-cast refractories

This study concerns high zirconia fused-cast refractories used in the glass industry. In situ temperature measurements have been performed in the casting structure during an actual casting of a tile. A two-dimensional mesh of the casting structure has been developed so as to perform numerical simulations. From temperature recordings, an interfacial heat transfer coefficient between the tile and the graphite mould has been determined, by an inverse method, by fitting the calculated temperatures with those measured. A similar procedure allowed the thermal conductivity and the heat capacity of the surrounding insulating medium to be determined. Then, the numerical model allowed the evolution of the temperature field, within the tile, to be determined. The influences of different parameters (mould thickness and thermal properties of the annealing medium) have been numerically tested, by comparison with the cooling-down kinetics of the tile.