Numerical analysis of pressure drop in separator type filter and estimation of its optimum separator height

Abstract

Separator-type HEPA filters are composed of elements which have square cross section bounded by two separator walls and partitioned by a filter medium. Therefore, it is possible to characterize pressure drop of a separator type air filter unit by studying the pressure drop of these filter elements. In the present work, the similarity law for the flow channels including a porous media was discussed and the dimensionless parameters which determine the pressure drop were derived. The dimensionless pressure drop was presented as a generalized-pressure drop diagram in terms of dimensionless parameters. Furthermore, the results of numerical analysis for the two-dimensional model filter were compared with those of experiments with two- and three-dimensional model filters. The prediction equation for optimum separator height, which is the most important factor for designing the filter unit, was presented as a function of filter media resistance and filter depth. © 1995, The Society of Chemical Engineers, Japan. All rights reserved.