Fully Developed Forced-Convection Heat Transfer in Cylindrical Packed Beds with Constant Wall Heat Fluxes

Abstract

Hydrodynamically and thermally fully developed forced-convection heat transfer in cylindrical packed beds with constant wall heat fluxes is theoretically examined on the basis of our previous two-dimensional, distributed parameter model taking into account the effects of non-Darcy, variable porosity and radial thermal dispersion. Several system parameters including the Prandtl number, Pr, the ratio of the thermal conductivity of solid to that of fluid, κ, the bed radius to particle diameter ratio, Γ, and the particle Reynolds number, Re_p, are varied. The adequacies of some approximations to the governing equations are also examined in detail. It is found that the effects of the aforementioned system parameters on the relationship between the Nusselt number and Re_pPr are the same as those observed for packed beds with constant wall temperatures, but values of the Nusselt number are generally greater than those obtained under the boundary condition of constant wall temperature, as long as values of Γ, κ and Re_pPr are kept constant.