Abstract
The axial motion of spherical packings in a mobile bed was studied by cinematography.
Upward and downward velocities, and absolute-value mean and root-mean-square velocities of the packings were evaluated through analysis of the axial motion of the packings. Disperision coefficients of the spherical packings were measured experimentally on the basis of the dispersion model.
The velocities of the spherical packings and the dispersion cefficients increased with increasing gas and liquid velocities and with increasing column diameter. On the other hand, the Peclet number, Pe=DpUpz/Epz, decreased with increasing gas and liquid velocities and column diameter.
On the assumption that the relationship between the mean particle velocity and the dispersion coefficient in the kinetic theory of gases is applicable to these phenomena, the Peclet number was expressed as a function of the particle holdup. Consequently, the correlations for each mean velocity and the dispersion coefficient were presented as a function of the holdups and the diameter ratio of the spherical packings to the column.
