FLOW THROUGH PACKED BEDS: WALL EFFECT ON DRAG FORCE.

This paper examines the wall effect on drag force for a flow of fluid through packed beds. The mathematical model previously given by Nield is extended to include wall effect. The value of drag force is calculated and plotted for different values of particle diameter: column diameter. The presence of the wall is found to have a profound effect on the drag force and this effect decreases with an increase in bed porosity. In order to minimize the wall effect, beds with large D/D//p ratios should be preferred. 6 refs.