Baling process of a belt-type baler based on a discrete element-multi-body dynamics coupling method

• The discrete element model of the silage corn feed mixture was accurately developed. • The multi-physical field coupling simulation of the baling device was conducted. • The dynamic bale formation mechanism of the belt-type baling device was revealed. The baling mechanism of silage corn in belt-type baling devices remains inadequately understood, particularly regarding the influence of material heterogeneity on bale formation efficiency. Existing studies often rely on empirical design and overlook the complex interactions among rigid components, flexible belts, and granular materials. To address this gap, this study employs a discrete element-multibody dynamics (DEM-MBD) coupling method to investigate the dynamic baling process. Based on the heterogeneous characteristics of silage corn, the material was categorized into six distinct components: plant leaves, corn kernels, cob cores, husks, stalk pith, and stalk rind. Their intrinsic parameters and particle size distributions were experimentally measured, and DEM simulation parameters were calibrated using physical tests and angle of repose validation. A rigid-flexible coupled dynamic model of the belt-type baling device was established, with contact between the belt and steel rollers defined via the Patch Set module to enable accurate rigid-flexible interaction modeling. The simulation revealed the multi-physical field coupling mechanism involving "rigid-flexible-granular" interactions and the mechanical response characteristics during bale formation. The results show that at a baling pressure of 0.72 MPa, belt speed of 1.4 m/s, and feed rate of 3.4 kg/s, the average bale density reaches 733 kg/m 3 , demonstrating that the device's structural and kinematic parameters satisfy the process requirements for silage corn baling. These findings provide theoretical support and engineering guidance for the optimized design and performance enhancement of silage feed baling devices.