(190f) Consolidation of Granular Material Subject to Thermal Cycling

Granular materials are ubiquitous, impacting a variety of industrial processing in the pharmaceutical, chemical, and construction industries, but also having implications in natural phenomena such as the formation of lunar regolith, dunes and beach sand. Recently, it has been found that cyclic variation of the temperature of a granular bed can cause static particle beds to consolidate ostensibly (increase its packing fraction) over time due to thermo-mechanical coupling. We employ experimental techniques and numerical simulation, using the thermal particle dynamics method (TPD), to study this phenomenon. In order to simulate many natural phenomena such as lunar regolith formation, one needs to determine a reasonable simulation depth of the bed which will yield realistic results yet be manageable computationally. Here we use penetration theory to estimate the required simulation bed height. Lateral periodic boundary conditions are used in our simulations to show that consolidation still occurs during vertical heating even in the absence of confining side walls.