The use of various published correlations to determine apparent thermal conductivities was found to give results of differing ma; magnitudes. For this reason when these values were utilized in the theoretical relationships proposed by McAdams:
tw-t2/tw-t1 = 0.692e-23.14X + 0.1312e-121.9X + 0.0535e-299.6X
in which X is defined as
X = (KaL/CpGoD2t)
For packed bed systems the results were found to be inconsistent.
In this investigation a dimensionless equation:
Ka/kg = 0.00105 (DpGo/εpμ)1.32
has been developed which permits the prediction of apparent thermal conductivities to air flowing through a 1 inch tube picked with glass beads. The equation gives satisfactory results for ratios of Dp/Dt from 0.15 to 0.22 and a modified Reynolds number of 526 to 3990.
The effect of voids in the packing material was studied and a porosity was included in the modified Reynolds number used in correlating the data.
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