Pattern Formation in Vertically Vibrated Granular Layers: Experiment and Simulation

摘要

We report on pattern formation in experiments and simulations of vertically vibrated granular layers. We find that initially flat vibrated layers lose stability to sub-harmonic standing wave patterns when the driv-ing acceleration is increased to about 2.5 times gravity. Patterns can be squares, stripes, hexagons, or localized structures (oscillons), depending on frequency and acceleration. Event deiven simulations show excellent quali-tative and quantitative agreement with the experiments.