Two-Phase Frictional Pressure Drop in Flooded-Bed Reactors:
A State of the art correlation
Chem. Eng. Technol. 21 (1998) 887-893
F. Larachi, Z. Bensetiti, B.P.A. Grandjean
Department of Chemical Engineering Laval University
Sainte-Foy Québec G1K 7P4 CANADA
Laboratoire des Sciences du génie chimique de Nancy
1 rue Granville BP 451, Nancy 54001 FRANCE

A state-of-the-art correlation for the prediction of frictional gas-liquid pressure drop in cocurrent upflow fixed bed reactors was derived based on a wide hydrodynamic data bank of flooded packed-bed reactors. The data bank, which contains more than 3,400 measurements, was constructed using information collected from 22 sources over the past 40 years. The correlation, which relied upon combination of dimensional analysis and artificial feedforward neural networks, was expressed as a two-phase friction factor function of the five most pertinent dimensionless groups (ReLG, Mo, St, FrL, XL). The prediction and generalization capabilities of the proposed correlation and the limits of existing literature correlations and models were demonstrated by systematic statisitical tests over the constructed data bank.

You can get the file to compute the frictional factor f LG The file contains the Fortran  source code along with the model parameter file.
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