CALIBRATION OF SOIL DISCRETE ELEMENT CONTACT PARAMETER IN RHIZOME MEDICINAL MATERIALS PLANTING AREA IN HILLY REGION

Abstract

Aiming at the lack of accurate and reliable discrete element simulation parameters in the study of the soilmachine interaction mechanism and the design of machinery in the planting areas of rhizomes in hilly mountainous areas, EDEM software was used to calibrate the parameters. The soil angle of repose test was used to calibrate the contact parameters between soil particles, and the soil sliding test was used to calibrate the contact parameters between soil and machinery. The Box-Behnken optimization method was used to establish the multiple regression model of the angle of repose and the sliding angle, and the optimal contact parameters between soil particles were obtained by solving the model. The optimal combination of contact parameters was used to conduct tests on the angle of repose and soil sliding angle and the errors between the simulation and physical tests were 3.94% and 3.66%, respectively. In order to further verify the accuracy of the calibrated and optimized discrete element model parameters, the rotary tillage ridge field test and the simulation test were used for comparative analysis, and the relative errors of the simulated test results and the field test results for ridge height, ridge top width, and ditch bottom width were obtained, respectively. 4.45%, 6.96%, 8.56%, the error is within the acceptable range. The rotary tillage and ridging effects are consistent in simulation and field tests, confirming the accuracy and reliability of the calibration of soil parameters.