The angle of repose in particle systems is a fundamental scientific problem in particle science. A deep understanding of its influencing factors and patterns of variation is of great significance for optimization in fields such as civil and chemical engineering. However, existing research based on experiments is limited by available types of particles and measurement methods, making it difficult to comprehensively reveal the impact regulations of various physical parameters on the angle of repose. This paper conducts a high-precision numerical study on the angle of repose in particle systems using the discrete element method (DEM), uncovering the most important particle property parameters that affect the angle of repose. DEM is a numerical method that directly simulates the motion of complex particle systems. Specifically, this study adopts a rolling friction coefficient to characterize the influence of non-sphericity on the simulation and validates the established model with existing experimental data. In addition, binary images of the heap projection in the vertical plane are utilized to calculate the angle of repose reasonably. Simulation results show that both sliding and rolling friction coefficients are positively correlated with the angle of repose. Increasing the sliding friction coefficient can double the angle of repose, while increasing the angle of repose caused by the rolling friction coefficient will reach an upper threshold. Once reaching this value, the angle of repose cannot be further increased. The particle's Young's modulus and restitution coefficient have a relatively small impact on the angle of repose. At the same time, this study employs the DEM to investigate the heat transfer characteristics of granular heaps. It is observed that during heating, the region with the highest heat flux within granular heaps migrates from the bottom to the top. These results reveal the most important factors affecting the angle of repose and can guide engineering optimization.

discrete element method  /  angle of repose  /  control variable method  /  granular heaps