An experimental investigation was made of temperature gradients in air streams being cooled while flowing through a cylinder of diameter 81 mm packed with high thermal conductivity (iron and copper) and low thermal conductivity solids of spheres

cylinders and Raschig rings. From the measured temperature gradients at various bed depths and radial posi-tions

and for the different particle sizes and flow rates

the effective thermal conductivity Ke

and the heat transfer coefficient of the wall hw

were determined by the integral

graphical and the direct-current electric analog methods. In the experimental range: Dp/Dt varied from 0.074 to 0.254 for the low thermal conductivity solids

from 0.12 to 0.2 for the high thermal con-ductivity solids; L/Dt varied from 5 to 15; Re number varied from 130 to 1400

corresponding to a linear velocity of 0.5- 1.6 meters per minute. If the arithmatic mean of the inlet and outlet temperatures was used as a qualitative temperature in the calculation

the effective thermal conductivity Ke

and heat transfer coefficient of the wall hw

could be correlated in the following equations: For low thermal conductivity solids: For high thermal conductivity solids: In case of cylinders and Raschig rings

the Dp in the above equations should be substituted by Dp and the constants 0.182 and 0.3 in the KG for- mulas should be changed to 0.22 and 0.38 correspondingly. A direct-current electric analog method was used in this paper

by which the temperature profiles of the bed could be calculated very con-veniently.