Estimating Correlation of Effective Thermal Conductivity on the Spherical Packed Bed Porous Media

Abstract

The correlation of an effective thermal conductivity (keff) on spherical packed bed porous media with stagnant fluid was proposed. Alumina-Cordierite ceramic ball (Al-Co) having average diameter (d) of 2.1 cm and porosity (Φ) of 0.468 was examined. The experimental procedure was operated based on ASTM E1225. The tested porous sample was sandwiched by references materials (Solid Brass, 70%Cu, 30%Zn). A higher temperature (TH) on the top of test set was obtained from wire heater with a constant electrical power of 350 W. The water cooling set was installed at the bottom of to generate a lower temperature (TL). Four previous models established from geometrical structure were compared to validate the present correlation. From experiment, it was found that keff decreased with increasing TH. Thus, the relation between keff and TH was appropriately proposed by a correlating linear-equation (keff/kf = 329.2(1-0.1028(TH/100)). Agreement between the present correlation and literature models was satisfied particular.