Abstract
The formation mechanism of particle packing structures in a drying process was analyzed by using a simulation for the drying behavior of particulate suspensions coupled with CIP method and DEM. It was cleared by the detailed investigation of the influences of suspension characteristics and particle properties that the high dens packing structure of particles was formed by the following three kinds of actions. a) The promotion of a rearrangement with increasing of ζ potential or decreasing of Debye length which define an interparticle interaction. b) The formation of ordering structure of particles in liquid with increasing of initial particle concentration of suspensions before drying. c) The increase of vertical capillary force with increasing of liquid surface tension and improving of particle wettability. On the other hand, the effect of particle surface roughness on particle packing structure was negligible because repulsive forces strongly acted on interparticle in liquid by hydrodynamic interaction and electric double layer. Polydisperse suspensions containing particles whose geometric standard deviation is larger than 1.1 formed high dense packing structures with increasing of the deviation of particle size, however, those particle beds were structurally heterogeneous in which particle size distribution became different at each height section.
