Li Shoutai, Hu Man, Liu Yan, Li Yunwu
Chongqing Key Laboratory of Agricultural Equipment for Hilly and Mountainous Regions, College of Engineering and Technology, Southwest University, 400715, Chongqing, People's Republic of China.
Agricultural Machinery Quality Control and Inspection Technology Center, Nanjing Research Institute for Agricultural Mechanization Ministry of Agriculture, 210000, Nanjing, People's Republic of China.
Sci Rep. 2024 Aug 5;14(1):18089. doi: 10.1038/s41598-024-69269-8.
The establishment of discrete element method (DEM) model for simulating the behavior of viscous soil can significantly contribute to the development of agricultural machinery, particularly in hilly areas worldwide. There is limited research on the parameter calibration of the DEM for purple soil in the Southwest China and its interaction mechanism between very narrow tine. Piling up test, rotating drum test and design-expert 12.0 software were used to design Plackett-Burman test, steepest climb test and Box-Behnken test successively. Combined with soil intrinsic parameter measurement test, soil simulation parameter calibration and optimization were completed. Based on the optimized DEM simulation parameters, the average relative errors of static repose angle and dynamic repose angle were 1.934 and 2.289%, respectively. The accuracy of parameter calibration results of DEM simulation was proved. Three kinds of very narrow tines were designed and processed. The interaction model and mechanism between soil-touch parts and soil was established. The average relative errors between the DEM simulation results of the forward resistance and disturbance area of the three soil-touch parts and the soil bin test results were 7.22% and 11.24%, respectively, which further proved that the calibration results of DEM parameters of purple soil and the interaction model with the soil-touch parts in this study were reliable. The physical and interaction parameters of slope cultivated purple soil in Southwest China were determined based on static-dynamic repose angle, providing more accurate parameters for study of soil-touch parts.
建立用于模拟粘性土行为的离散元法（DEM）模型，对农业机械的发展具有重要意义，特别是在全球丘陵地区。目前针对中国西南地区紫色土离散元法参数标定及其在极窄齿间相互作用机制的研究较少。依次采用堆土试验、转鼓试验和Design-Expert 12.0软件进行Plackett-Burman试验、最速上升试验和Box-Behnken试验。结合土壤固有参数测量试验，完成了土壤模拟参数的标定与优化。基于优化后的离散元法模拟参数，静态休止角和动态休止角的平均相对误差分别为1.934%和2.289%，证明了离散元法模拟参数标定结果的准确性。设计并加工了三种极窄齿，建立了土壤接触部件与土壤之间的相互作用模型和机制。三种土壤接触部件的前进阻力和扰动面积的离散元法模拟结果与土槽试验结果的平均相对误差分别为7.22%和11.24%，进一步证明了本研究中紫色土离散元法参数标定结果及其与土壤接触部件相互作用模型的可靠性。基于静态-动态休止角确定了中国西南地区坡耕地紫色土的物理参数和相互作用参数，为土壤接触部件的研究提供了更准确的参数。
