Radial variation in porosity in annular packed beds

This paper describes the results of a study of the variation in the radial direction in the porosity of annular packed beds. A comparison is made between the predictions by a number of empirical correlations found in literature, the porosities obtained from physical experiments and the porosities obtained from the analysis of numerically generated packed beds. It is concluded that the numerical annular packed beds can be considered as acceptable representations of the actual annular packed beds. From the comparison between a number of exponential correlations proposed by various authors for the variation in the radial direction in the "averaged" porosity and the numerical results it is recommended that the correlation proposed by Hunt and Tien be used to describe the variation in the radial direction in the porosity. It is, however, also recommended that a further thorough study be conducted to develop a more detailed understanding of the porosity characteristics of annular packed beds. (C) 2008 C.G. du Toit. Published by Elsevier B.V. All rights reserved.