A simplified correlation for fixed bed pressure drop

Abstract

An experimental study was conducted on the pressure drop characteristics of a variety of vertical packed beds in turbulent flow of air. The materials of different particle diameter, D p, with a range of sphericity Φ, 0.55 ≤ Φ ≤ 1.00 were used in random loose packing to produce beds of different lengths, L, with a range of porosity, ε, 0.36 ≤ ε ≤ 0.56. In the covered test cases the cross-sectional velocity distribution at the exit plane of the packed beds and the pressure drop Δ P Bed were measured in a particle Reynolds number range of Re p, 675 ≤ Re p ≤ 7772. The particular emphasis of the study was given to determine the influence of ε, Φ, D p, L, Re p on Δ P Bed. In this respect the measurements of Δ P Bed were compared with the well-known Ergun's Equation and the data were expressed in terms of correlations through introduced dimensionless parameters of pressure coefficient, Δ P ⁎ and exit Reynolds number Re exit. The proposed correlations of Δ P ⁎ = Δ P ⁎( εRe p D p / L) and Re exit = Re exit( Re p D p / L) are found to be appropriate for the determination of Δ P Bed and mean exit velocity, U, respectively with an acceptable fit of experimental data in an error margin less than ± 20%. The methodology is presented in this paper as an alternative approach to the available literature on packed beds.