Inter-Particle Liquid Bridges - A Building Block to Model Complex Mixing Phenomena

Erosion and rupture, the most common failure modes observed previously in particle agglomerates correspond to sustained removal of small surface fragments and instantaneous shatter of the agglomerate respectively; both cohesive mechanisms due to failure initiating at a dry-dry or a wet-wet interface. However recently, an alternate adhesive mechanism of wet-dry failure has been observed in partially infiltrated sparse agglomerates due to infiltration-induced rearrangement at the advancing liquid interface. To probe interfacial phenomena at the scale of the units comprising the interface, we adopt a more fundamental approach treating the agglomerate as an assimilation of individual dry (in the core) and wet contacts (in the shell). Dry contacts are well understood. We concern ourselves specifically with characterization and simulation of the wet contacts, measured in the lab as scale-able liquid bridges between particles. We employ these fundamental interactions to simulate real agglomerates, monitoring them vis-ŕ-vis the criteria characteristic of a failure mechanism. Incorporation of agglomerate distortion dynamics enables accurate estimation of agglomerate strengths in dispersive flow fields. This model depicts well the strengthening/weakening of agglomerates by introduction of liquid bridges at varied loci within the porous structure.