DEM simulation of maize milling in a hammer mill

Abstract

The Discrete Element Method (DEM) is an advanced simulation tool for modeling particle systems, with breakage models becoming increasingly robust and widely applied. This study presents the first DEM-based simulation of continuous maize milling in a hammer mill, integrating a systematically calibrated Tavares breakage model. A Particle Replacement Model (PRM) was employed to simulate the fragmentation process, with parameters calibrated through a rigorous experimental and numerical approach. Experimental tests were conducted on a laboratory-scale hammer mill, measuring power draw and particle size distribution (PSD) across different screen apertures and mass flow rates. The simulations, implemented in Rocky DEM, successfully predicted power consumption trends and accurately replicated the PSD, validating the model’s capability to describe complex milling dynamics. The results provide new insights into the influence of operating conditions on milling performance, establishing a validated numerical framework for optimizing hammer mill operations. This work lays the foundation for future DEM simulations of pilot- and industrial-scale maize milling processes.