Study of the effect of interaction coefficients on dynamic stacking behaviour under various particle shapes

Abstract

The angle of repose (AoR) is a characteristic parameter of powder and granular materials and is the most intuitive manifestation of particle stacking behaviour. When the particle morphology and interaction coefficient change, the particle stacking morphology and AoR also change. In this paper, to obtain the factors affecting the dynamic stacking behaviour of gangue particles, relying on the injection AoR measuring device and the dynamic stacking simulation model, we designed the orthogonal simulation experiments with the restitution coefficient of particle-particle (PPRC), the static friction coefficient of particle-particle (PPSF), the rolling friction of particle-particle (PPRF), the restitution coefficient of particle-wall (PWRC), the static friction coefficient of particle-wall(PWSF), and the rolling friction coefficient of particle-wall (PWRF) as the influencing factors. Taking the AoR as the evaluation index, we simulated 125 sets of dynamic stacking simulation experiments with different particle morphologies. We obtained the interaction coefficient schemes matching the experiments and the influence laws of the six interaction coefficients on the evaluation index. Among them, the static friction coefficient has the most significant influence. The prediction of the stacking shape formula for rectangular particles was verified, and the error between the prediction result and the actual stacking result was within 15 %, which indicates that other combinations of interaction coefficients can be based on the formula for stacking shape prediction. The model and the prediction method guide the study of the stacking morphology and kinematic behaviour of other particles.