The Spot Model for random-packing dynamics

@article{citeulike:2582922, abstract = {The diffusion and flow of amorphous materials, such as glasses and granular materials, has resisted a simple microscopic description, analogous to defect theories for crystals. Early models were based on either gas-like inelastic collisions or crystal-like vacancy diffusion, but here we propose a cooperative mechanism for dense random-packing dynamics, based on diffusing "spots" of interstitial free volume. Simulations with the Spot Model can efficiently generate realistic flowing packings, and yet the model is simple enough for mathematical analysis. Starting from a non-local stochastic differential equation, we derive continuum equations for tracer diffusion, given the dynamics of free volume (spots). Throughout the paper, we apply the model to granular drainage in a silo, and we also briefly discuss glassy relaxation. We conclude by discussing the prospects of spot-based multiscale modeling and simulation of amorphous materials.}, author = {Bazant, Martin Z. }, booktitle = {Advances in Disordered Materials}, citeulike-article-id = {2582922}, doi = {http://dx.doi.org/10.1016/j.mechmat.2005.06.016}, journal = {Mechanics of Materials}, keywords = {grain, model, qualifier}, month = {}, number = {8-10}, pages = {717--731}, posted-at = {2008-03-24 22:30:08}, priority = {2}, title = {The Spot Model for random-packing dynamics}, url = {http://dx.doi.org/10.1016/j.mechmat.2005.06.016}, volume = {38}, year = {2006} }

TY - JOUR ID - citeulike:2582922 L3 - citeulike-article-id:2582922 TI - The Spot Model for random-packing dynamics T2 - Advances in Disordered Materials JF - Mechanics of Materials VL - 38 IS - 8-10 SP - 717 EP - 731 N2 - The diffusion and flow of amorphous materials, such as glasses and granular materials, has resisted a simple microscopic description, analogous to defect theories for crystals. Early models were based on either gas-like inelastic collisions or crystal-like vacancy diffusion, but here we propose a cooperative mechanism for dense random-packing dynamics, based on diffusing "spots" of interstitial free volume. Simulations with the Spot Model can efficiently generate realistic flowing packings, and yet the model is simple enough for mathematical analysis. Starting from a non-local stochastic differential equation, we derive continuum equations for tracer diffusion, given the dynamics of free volume (spots). Throughout the paper, we apply the model to granular drainage in a silo, and we also briefly discuss glassy relaxation. We conclude by discussing the prospects of spot-based multiscale modeling and simulation of amorphous materials. KW - grain KW - model KW - qualifier AU - Bazant, Martin PY - 2006/0// UR - http://dx.doi.org/10.1016/j.mechmat.2005.06.016 ER -