Values of dispersion coefficients from theory and experiment

Values of Dispersion Coefficients from Theory and Experiment 

This relation is plotted in Fig. 2.20, the first term having only a small effect in the Reynolds number range shown, except at low Schmidt numbers. 

Dispersion coefficients for packed beds are usually plotted in the form of a similar dimensionless group, the Peclet number udp/DL, which uses the diameter of the particles of the bed dp as the characteristic length rather than the bed diameter. Graphs of experimentally measured values of both axial and radial Peclet numbers plotted against Reynolds number, also based on particle diameter, are shown in Volume 2, Chapter 4. 

Another interesting application of the data in Fig. 2.20 for dispersion coefficients in turbulent flow is in calculating the mixing that occurs in long pipelines. Many refined petroleum products are distributed by pipelines which may extend over hundreds of kilometres. The same pipeline is used to convey several different products, each 

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