- Howle, L.E. and Georgiadis, J.G., Natural convection in porous media with anisotropic dispersive thermal conductivity,
International Journal of Heat and Mass Transfer, vol. 37 no. 7
pp. 1081 - 1094 [0017-9310(94)90194-5] .
(last updated on 2007/04/06)
A numerical simulation is undertaken in order to study the effect of anisotropy of the effective thermal conductivity tensor on heat transport in the porous medium Rayleigh-Benard problem. The momentum equation includes an inertial drag (Forchheimer) term. The effective thermal conductivity tensor, in the energy equation, contains an isotropic stagnant component and a hydrodynamic dispersive component with principal axes aligned with the local velocity vector and with magnitude proportional to the local amplitude. A parametric study of two-dimensional steady cellular convection reveals the following . (1) Dispersion increases the net heat transfer after a Rayleigh number approximately equals 100-200. As the degree of anisotropy of the effective thermal conductivity is increased, the wall averaged Nusselt number is decreased. (2) Using the available Rayleigh number-wavenumber variation data does not affect the divergence between simulation and experiment.
Porous materials;Thermal conductivity;Anisotropy;Hydrodynamics;Tensors;