A finite‐discrete element model for simulating collision and fragmentation of nanoparticle agglomerates

Abstract

The fragmentation/adhesion behavior of nanoparticle agglomerate collision, which is challenging to model, is a crucial factor affecting fluidization. In this study, a discrete‐finite element method (FDEM) based cohesive crack model is developed to simulate normal collisions between a complex agglomerate (around 1 mm) and a wall. In the FDEM model, the complex agglomerate is built from primary agglomerates (around a few micrometers), whose adhesive force and Young's modulus are measured by an atomic force microscope (AFM). The simulation results including fragmentation morphology and plastic deformation agree well with the collision experiments. Finally, the sensitivity of the model is tested, including adhesive force, solid holdup, and Young's modulus. Fragment distribution is found to fit well with a two‐parameter Weibull function and damage ratio is found to have a polynomial relation with a modified Weber number. The model output shows a potential to be utilized in macroscopic model.