NUMERICAL-ANALYSIS OF NEAR-WALL CHANNELING IN A PACKED-BED

Regularities imposed by an external wall on the random distribution of particles in a packed bed lead to anisotropic wall effects of the bed . The resulting deviations of near-wall porosity from the average bed- porosity markedly affect the average velocity profile, not only near t he wall but also some distance into the bed itself. The effect of wall channelling due to such variations in porosity near external boundari es is predicted by means of two different numerical solution methods f or a unified model for granular porous media. The results are shown to compare favourably to experimental and numerical results reported in the literature.