DEM parameter acquisition and calibration of corn stalk non-spherical particles using particle trajectory tracking.

The restitution coefficient is one of the microphysical properties that must be specified for a discrete element model simulation. The more accurate the input, the more accurate the simulation results are. Due to the differences in shape and surface roughness between the corn stalk particle model built-in EDEM software and the actual corn stalk, the simulation will be distorted if the measured recovery coefficients are directly introduced into the EDEM software for simulation. To address this issue, this paper presents experimental measurements of the collision behavior between the intermodal tissue, pith, and nodal tissue particles and the horizontal substrate based on kinematic principles and with the aid of high-speed camera technology to reconstruct the trajectory of the particles during free fall and bounce. Utilizing EDEM software to simulate the free fall and bounce processes, a quadratic polynomial prediction model of the recovery coefficient input values and calculated values was established. Combined with the simulation and physical tests, the coefficients of restitution between the pith and the iron plate and pith surface are 0.559, 0.767. The collision restitution coefficients were determined to be 0.767, 0.616, and 0.784 for the collision between the rind and the iron plate, rind surface, and pith surface, respectively. 0.549, 0.705, 0.687, and 0.723 for the collision restitution coefficients between the node and the rind surface, pith surface, and node surface, respectively. The calibration restitution coefficient was input to EDEM software for the simulation test, and the relative error between the simulation results and the physical examination was within 4.15%. The particle model created and the restitution coefficients calibrated can be used as a reference for designing a corn stalk processing machine and the discrete-element study on the motion of corn stalk particles inside such devices. [ABSTRACT FROM AUTHOR]