ANALYSIS AND CALIBRATION OF DISCRETE ELEMENT PARAMETERS FOR YANHUSUO BASED ON STACKING TESTS

To address the lack of contact parameters for yanhusuo during the mechanization process, its basic physical and contact parameters were derived through both theoretical calculations and practical measurements. Utilizing 3D scanning technology, a 3D model of yanhusuo was obtained. A discrete element model was then established using an automatic filling method. The key factors influencing the stacking angle of yanhusuo were identified using Plackett-Burman tests. The optimal ranges for these factors were determined through the steepest ascent experiment, and a quadratic regression model for the stacking angle was developed using response surface methodology (RSM) based on a rotational orthogonal experimental design. The optimized parameters - a restitution coefficient of 0.481, static friction coefficient of 0.508, and rolling friction coefficient of 0.029 - yielded a stacking angle of 21.23°. Experimental validation showed a relative error of just 0.86% between the simulation and physical tests. These results demonstrate that the discrete element model and calibrated parameters closely replicate real-world conditions, providing valuable insights for the mechanical design of yanhusuo planting and harvesting equipment.