NUMERICAL-MODEL FOR COMBINED CONDUCTIVE AND RADIATIVE HEAT-TRANSFER IN ANNULAR PACKED-BEDS

A numerical model is developed for quantitatively analyzing combined c onductive and radiative heat transfer in concentric annular packed bed s. A packed bed is considered to be a continuous medium for heat trans fer, but the porosity distribution within a packed bed is taken into a ccount. To examine the validity of the proposed model, combined conduc tive and radiactive heat transfer through annular packed beds of cordi erite or porcelain beads is analyzed numerically using finite differen ces under conditions corresponding to heat transfer experiments of the se packed beds. The resultant temperature profiles and heat transfer c haracteristics are compared with the experimental results.