A theoretical investigation of enhancement of mass transfer from a packed fed using acoustic oscillations

This paper describes a theoretical investigation of the possibility of impr oving the performance of packed bed dryers using acoustic oscillations. It was motivated by the increasing interest in the use of acoustic oscillation s to improve the performance of energy-intensive, industrial processes. Sou nd propagation in a packed bed was modelled as propagation through a porous medium. The effect of acoustic oscillations on the drying rate was then in vestigated by numerically integrating the heat and mass transfer equations. The model used quasi-steady correlations for heat and mass transfer. The r esults show that threshold values for void fractions and sound pressure lev els exist, above which significant increase in drying rate can be obtained. The increase in mass transfer decreases with effective particle diameter.