2001 journal article

Effects of heterogeneity in forced convection in a porous medium: Parallel-plate channel, asymmetric property variation,and asymmetric heating

Journal of Porous Media, 4(2), 137–148.

By: D. Nield* & A. Kuznetsov

co-author countries: New Zealand 🇳🇿
Source: NC State University Libraries
Added: August 6, 2018

The effects of variation (in the transverse direction) of permeability and thermal conductivity on fully developed forced convection in a parallel plate channel or circular duct filled with a saturated porous medium is investigated analytically on the basis of a Darcy model. Previous work on the case of symmetric property variation and symmetric heating is now supplemented by a study of the case of asymmetric property variation, for both symmetric and asymmetric heating, lsoflux and isotemperature boundary conditions are treated in turn. For the isofiux case, it is found that both permeability variation and conductivity variation lead to a reduction in the value of the Nusselt number Nu based on mean properties, but for the isotemperature case the situation is more complicated. For the isoflux case and permeability variation only, Nu is independent of the degree of asymmetric heating as represented by a flux ratio τ, but in the case of conductivity variation Nu is strongly dependent on τ and the degree of conductivity variation. In the case of isotemperature boundary conditions no fully developed solution exists when both the property variation and the heating are asymmetric.