More-Detailed Analysis of the Effects of Inertia on the Filtration Efficiency of Granular-Bed Filters

摘要

The filtration efficiency of granular bed filters is usually considered as the sum of the effects of inertia, diffusion, gravity, interception and, perhaps, some additional mechanisms. The effect of inertia is important and the generally accepted opinion is that for faster flows, with stronger acceleration fields, this effect increases. This work indicates that for certain ranges of the Stokes number faster flows with stronger accelerations lead to lower contribution to filtration efficiencies by the inertia effect. The reason for this is shown to be the inflection points on the stream lines, which reverse their curvature and thus the effect of inertia. (ERA citation 07:054802)