CALIBRATION AND OPTIMIZATION OF DISCRETE ELEMENT PARAMETERS FOR TIGER NUTS

To improve the accuracy of discrete elemental simulation parameters for tiger nut seeds, this study suggests the measurement of the triaxial dimensions of tiger nut seeds using MATLAB. This method proves exhibiting a maximum error of no more than 0.16% compared to the traditional measurement techniques. Experimental measurements were used to obtain the basic physical parameters of the seeds. Physical tests on the angle of stacking of tiger nut seeds were conducted. A discrete meta-model for tiger nut seeds was constructed. The Plackett-Burman test and the steepest climb test were used to identify critical parameters affecting the angle of accretion and to delineate the optimal range of parameters impacting larger parameters proportionately. The optimum values for the coefficient of static and rolling friction between tiger nut seeds were established at 0.32 and 0.24, respectively, using response surface methodology. The average tangent of the simulated stacking angle obtained was 0.731 in three tests were carried out using the optimised parameters, representing a mere 0.41% deviation from the physical test average of 0.734. The experimental outcomes confirm that these parameters can provide reliable data for discrete meta-simulation experiments involving tiger nut seeds.