An Experimental and Numerical Study for Discrete Element Model Parameters Calibration: Gluten Pellets

Discrete element method (DEM) simulation is widely used to calculate the flow characteristics of particles under certain conditions. DEM input parameters are the prerequisite for the accurate modeling and simulation of particles. In order to explore the mechanical properties and breaking behavior of gluten pellets, the pellet material property, the interaction parameters of pellet-stainless steel and pellet-pellet (multi-spheres autofill model), and the bonding parameters (bonded particle model) were calibrated by experiments and simulations. The relative error of the angle of repose, the breaking displacement, and the breaking force between simulated and experimental values were 0.28%, 0.66%, and 1.09%, respectively. Based on the regression analysis in the Design-Expert 12.0 software, the relationships among evaluating indicators (angle of repose, breaking displacement, and breaking force) and their corresponding influencing factors were established, respectively. Meanwhile, the feasibility of applying the interaction parameters of the multi-spheres autofill model to the bonded particle model was verified through the free fall test, the inclined plane sliding test, and the inclined plane tumbling time test. This work can provide a reference for the design of pellet feed processing and transportation machinery.