Abstract:The contact parameters affect the discrete element simulation results of controlled-release fertilizer particles. In order to accurately simulate the mechanical behavior and motion law of controlled-release fertilizer particles, the contact parameters of controlled-release fertilizer particles were calibrated and experimented based on the discrete element method. Firstly, the basic model of controlled-release fertilizer discrete elements was established, and the contact parameters between controlled-release fertilizer particles and PVC panels were calibrated in EDEM by combining bench and simulation experiment. Secondly, the collision recovery coefficient, static friction factor and rolling friction factor between controlled-release fertilizer particles and PVC plate were measured by collision bounce experiment, slope slip experiment and inclined rolling experiment to be 0.539, 0.507 and 0.105, respectively. Finally, through the accumulation experiment, the steepest climbing experiment and the orthogonal rotation combination experiment, the collision recovery coefficient, static friction factor and rolling friction factor between controlled-release fertilizer particles were obtained as 0.38, 0.25 and 0.09, respectively, and verified by bottomless cylinder lifting experiment and fertilizer discharge bench experiment. The experiment results showed that the relative error between the actual value of the accumulation angle and the simulation result was 1.54%, and the relative error between the actual value of the discharge amount and the simulation result at the four speeds was 4.38%, 4.23%, 4.41% and 4.36%, respectively, and the contact parameters of the calibrated controlled-release fertilizer were accurate and effective, which can provide data and model support for the simulation of controlled-release fertilizer discrete elements.