Influence of pore structure on drying kinetics: A pore network study



A pore network model for convective drying is applied to investigate the influence of structure on drying behavior. The isothermal drying model is based on the work of Prat, and uses invasion percolation concepts, neglecting any viscous or gravitational effects. Pore structures of different pore-size distribution and coordination number are studied in two- and three-dimensions. Results are given as phase distributions or moisture profiles during drying, as well as drying rate curves. Significant differences in drying kinetics are reported for a variation in coordination number of monomodal networks. Bimodal pore structures can produce dramatically higher drying rates, but only for certain spatial correlations of small and large pores. Finally, influence of product thickness and importance of boundary layer modeling are addressed. © 2007 American Institute of Chemical Engineers AIChE J, 2007