Simulations of pattern formation in vibrated granular media

We present simulations of peak pattern formation in vibrated two-dimensional (2D) granulates and measure the dispersion relation of the pattern for various frequencies, accelerations, cell sizes, and layer heights. We report the first quantitative data from numerical simulations showing an interesting dependence of the pattern wavelength on the acceleration and the system size. Our results are related to recent experimental findings and theoretical predictions for gravity waves.