Effective Heat Transfer Parameters in Beds Packed with Spher

ABSTRACT:
Effective radial thermal conductivity and wall heat transfer coefficient for
packed bed of non reacted material, 4.8mm alumina spheres, were
experimentally determined at high temperatures up to 850 ºC for flow rates
giving particle Reynolds numbers in the range of 10 – 220. Radial temperature
profiles were measured at various axial positions. The results were analysed
on the basis of a two-dimensional pseudohomogeneous non-plug flow model,
where velocity profile take into account. Over these ranges both parameters,
λer and αw, showed significant dependence on gas flow rates for all different
wall temperatures and these dependencies were predicted well by correlations
with particle Reynolds number.

Effective Heat Transfer Parameters in Beds Packed with Spher