Authors

Abstract

In order to improve the accuracy of discrete element simulation of stubble cleaning soil-engaging parts of corn planter in wheat stubble field, taking the soil straw of Huang-Huai-Hai as the research object, the method of combining physical repose angle with EDEM simulation test was adopted, and the Hertz-Mindlin with bonding contact model was selected to calibrate the simulation contact parameters. Plackett-Burman was used to screen out the main factors that had a significant impact on the test indicators. Design-Expert was used to conduct a central combination test on the screening factors, and regression analysis and significance test were performed on the simulation results to find out the optimal combination of test indicators. The factor screening test showed that the primary and secondary factors affecting the soil repose angle were soil rolling friction factor, soil-device static friction factor, soil static friction factor and soil normal stiffness per unit area. The primary and secondary order of the factors affecting the straw repose angle was the device-straw rolling friction coefficient, the device-straw restitution coefficient, and the straw static friction coefficient. The significant test showed that the soil rolling friction coefficient was 0.574, the soil static friction coefficient was 0.93, the soil-device static friction coefficient was 0.373, the soil normal stiffness per unit area was 9.5×109, and the relative error between the optimized parameter simulation test and the actual test was 3.1%. The straw static friction coefficient was 0.598, the device-straw restitution coefficient was 0.754, the device-straw rolling friction coefficient was 0.11, and the relative error between the optimized parameter simulation test and the actual test was 1.45%.

Abstract in Chinese

为提高麦茬地玉米播种机清茬触土部件离散元仿真模拟的准确性，以黄淮海土壤秸秆为研究对象，采用物理堆积角与EDEM仿真试验相结合的方法，选用Hertz-Mindlin with bonding接触模型对仿真接触参数进行标定。通过Plackett-Burman 筛选出对试验指标影响显著的主要因子，运用Design-Expert对筛选因子进行中心组合试验，对仿真结果进行回归分析与显著性检验，找出试验指标最优的组合。因素筛选试验表明对土壤堆积角影响因素主次顺序为土壤滚动摩擦因数、土壤-装置静摩擦因数、土壤静摩擦因数、土壤单位面积正向刚度；对秸秆堆积角影响因素主次顺序为装置-秸秆滚动摩擦因数、装置-秸秆恢复系数、秸秆静摩擦因数。显著性试验表明土壤滚动摩擦因数为0.574、土壤静摩擦因数为0.93、土壤-装置静摩擦因数为0.373、土壤单位面积正向刚度为9.5×109，优化后的参数仿真试验与实际试验相对误差为3.1%。秸秆静摩擦因数为0.598、装置-秸秆恢复系数为0.754、装置-秸秆滚动摩擦因数为0.11，优化后的参数仿真试验与实际试验相对误差为1.45%。