Flow uniformizing distribution panel design based on a non-uniform porosity distribution

Abstract

The conditions required for a flow resistance element to uniformize a non-uniform flow in a two-dimensional channel were derived in terms of a non-uniform porosity profile. The validity of this approach was confirmed through a numerical analysis over a wide range of parameter conditions. The proposed equation for the non-uniform porosity distribution gave satisfactory results for a wide variety of velocity profiles at the channel inlet. For sufficiently thick orifices, the equation was valid over a wide range of average porosities, from 0.3 to 0.6. For thin orifices, satisfactory uniformity was obtained only for a mean effective porosity over a narrow range of 0.42-0.48. Two different methods of generating variable porosity, using a constant hole size plus variable blocking plates or using a constant blocking plate size plus variable holes, did not show any appreciable difference in results. (C) 2014 Elsevier Ltd. All rights reserved.