Lateral dispersion in liquid flow through packed beds at Pem <1,400

The values of the ratio between transversed dispersion coefficient, DT, and molecular diffusion coefficient, Dm, in packed beds are independent of Schmidt number, Sc, in the range Sc>500, but strongly dependent on Sc for 140<Sc<500. The difference in behavior between beds of spheres and beds of sand resulting from the difference in particle shape is slight. The dispersion in a bed with a mixture of particle sizes follows the prediction for beds of nearly monosized particles, if the average particle size is used in the calculation of Peclet number, Pem.