Axial effective thermal conductivities of packed beds

Experimental investigations have been carried out to measure axial effective thermal conductivities of packed beds for a number of particles and catalyst pellets. Measurements were made for three gases (air, nitrogen and carbon dioxide) in beds packed with ball bearings, copper chromite, chromia alumina, alumina hollow cylinders and alumina spheres. A glass vacuum vessel was employed for most measurements, but a thin wall stainless steel vessel was used in a few experiments. Empirical correlations to predict the axial effective thermal conductivity of packed bed reactors have been derived from the experimental results