%0 Journal Article
%T A Reconciliation of Packed Column Permeability Data: Deconvoluting the Ergun Papers
%A Hubert M. Quinn
%J Journal of Materials
%D 2014
%I Hindawi Publishing Corporation
%R 10.1155/2014/548482
%X In his 1952 publication, Ergun made the following proclamation: ¡°Data of the present investigation and those presented earlier have been treated accordingly, and the coefficients and have been determined by the method of least squares. The values obtained are and, , representing 640 experiments.¡± In this paper, we demonstrate that because his experimental methodology was flawed, the corrected values, which his experimental results would otherwise have established for these coefficients, are significantly higher. This is, in part, because Ergun¡¯s reporting of his measured data was ambiguous with respect to the embedded coefficients and . In addition, this ambiguity made it difficult for any subsequent researcher to figure out the true meaning of his empirical results which, in turn, resulted in his choice of the values for these coefficients being accepted by default in the scientific community. 1. Introduction The Ergun equation is unquestionably the most popular equation in use at this time to represent the relationship between pressure drop and resultant fluid flow in packed beds, when the fluid profile contains significant contribution from kinetic effects. In addition, most engineering departments at major universities and third level educational institutions throughout the world offer a teaching module which has as its focus the now famous ¡°Ergun equation.¡± The engineering literature, both chemical and otherwise, is replete with references to the equation and many of the studies reported therein have used it as a benchmark, against which to compare and contrast their empirical results. The equation was developed by Sabri Ergun in the late 1940s/early 1950s. It was derived, in part, from experimental measurements and, in part, from theoretical postulates. Ergun¡¯s initial paper was published in 1949 in collaboration with Orning. In two follow-up papers published in 1951 and 1952, Ergun reported his empirical results of enormous amounts of experimental runs aimed, in part, at calibrating the equation in terms of its two built-in coefficients. In this paper, we review these papers on this subject matter which we refer to collectively as the ¡°Ergun papers.¡± The first empirical data on the relationship between fluid flow rate and pressure drop across a packed bed was reported by Darcy in 1856 [1]. The resultant Darcy law states that when the flow is streamline, the fluid flow rate through a packed bed is proportional to the pressure drop across the bed. The law has limitations, however, because it only applies to streamline flow and, in addition, tells
%U http://www.hindawi.com/journals/jma/2014/548482/