Calibration and experiment of the contact parameters for the discrete meta-simulation of peanut pods during harvest in saline soils

In this study, a simulation model of peanut pod particles during harvest in saline soil was tested to calibrate contact parameters. Discrete meta-fill models of peanut pods were generated by a 3D meter and EDEM software. The range of values of contact parameters for peanut pods was measured by conducting collision and other tests using a homemade test rig. The parameters that affect the significance of the simulation process of stacking angle were screened by the Plackett-Burman experiment, the steepest ascent experiment, and the Box-Behnken experiment. An optimization test determined the optimal simulation model parameters: The peanut pods had a Poisson’s ratio of 0.386 and a shear modulus of 3.04 MPa. The coefficient of recovery for pods-pods collisions was 0.335, the coefficient of static friction was 0.854, and the coefficient of rolling friction was 0.346. The coefficient of recovery of collision between the pods-65Mn steel was 0.339, the coefficient of static friction was 0.589, and the coefficient of rolling friction was 0.159. The test results showed a relative error of 0.42% between the stacking angle bench and simulation tests. The results can provide data support for studying the discrete metamaterial characterization of peanut pods.