Comparative analysis of porosity coarse-graining techniques for discrete element simulations of dense particulate systems

The discrete element method (DEM) is a well-established approach to study granular materials in numerous fields of application; each particle modelled individually predict the overall behaviour. This behaviour can be then extracted by averaging, or coarse graining, sample using suitable method. choice appropriate coarse-graining entails compromise between accuracy and computational cost, especially large-scale simulations typically required industry. A number methods have been proposed literature, these are reviewed categorized this work. Within contribution, two novel porosity strategies including voxel where secondary dense grid “pixel cells” implemented adopting binary logic for graining hybrid both analytical formulas pixels utilized. compared with four schemes that documented centroid method, an which solves diffusion equation employs averaging kernels. validated problems three dimensions through comparison “accurate” It shown that, once validated, approximate exact solutions quite accurately; however, there high cost associated adjusted allowing user decide time. detailed presented all six considering “accuracy”, “smoothness” “computational cost”. Optimal parameters obtained methods, recommendations DEM samples discussed.