关键词: 离散元, 堆积角, 土壤, 响应面, Plackett-Burman试验

Abstract:  In order to establish the soil discrete element model accurately and obtain the simulation parameters in soil discrete element simulation, thePoissons ratio and stacking angle of soil wereobtained by real soil direct shear test and stacking test. Taking the stacking angle as the response value, the relevant parameters of discrete soil elements were calibrated based on response surface optimization. The PlackettBurman test, the steepest climbing test, and the BoxBehnken test were designed in turn by using Design Expert software to obtain the optimal combination of soil parameters. The regression model was optimized with the stacking angle as the target, and a set of optimal solutions wereobtained. Finally, the internal friction angle of soil is 19°, Poissons ratio is 040, the cohesion of soil is 9.06, JKR surface energy of soil contact model is 3.927 J/m, soilsoil recovery coefficient is 0.332, and the soilsoil static friction coefficient is 0.719. The comparison between the actual pileup angle test and the optimal solution simulation pileup angle test showshigh similarity in pileup angle and pileup angle shape. It proves the feasibility of this simulation calibration and lays a foundation for the subsequent discrete element simulation of agricultural machinery.

Key words: discrete element, accumulation angle, soil, response surface, PlackettBurman test