Abstract: In order to explore the influence of tilling parameters of vertical rotary tilling blade on its stress and soil crushing effect, a discrete element model of vertical tilling blade operation was firstly established, and the resistance and torque of rotary tilling blade were analyzed. By designing orthogonal rotary test, the influence of working parameters of vertical rotary blade on rotary resistance, torque, power and soil breakage rate was obtained and a mathematical model was established. The model could be used to predict data and guide operations. Through response surface analysis and mathematical model analysis, single blade power and soil crushing rate of vertical rotary tillage cutter were optimized, and the optimal operating parameters were obtained as follows: forward speed 1.2 m/s, tool speed 307.141 r/min, tillage depth 25 cm, power of vertical rotary tillage cutter 7.042 kW, soil crushing rate 80.85%. The optimal working parameters were put into the simulation test, and the relative error of the predicted power and the simulated power was 397% and the relative error of the soil breakage rate was 3.45%, which verified the availability of the prediction model.

Key words: discrete element, vertical rotary blade, tillage resistance, orthogonal test, response surface

摘要： 为探究立式旋耕刀作业参数对其受力情况及碎土效果的影响，建立立式旋耕刀作业的离散元模型，并对其所受阻力、扭矩的变化规律进行分析；通过设计正交试验，得到立式旋耕刀工作参数对其阻力、扭矩、作业功率及碎土率的影响，并建立相应的预测模型。通过响应面分析和预测模型对立式旋耕刀作业功率和碎土率进行参数优化，得到最佳工作参数为：前进速度1.2 m/s，刀具转速307.141 r/min，耕深25 cm，模型预测立式旋耕刀作业功率为7.042 kW，碎土率为8085%。将最佳工作参数代入仿真试验，对比试验数据得到功率的模型预测值与仿真值间的相对误差为3.97%，碎土率的相对误差为3.45%，验证了预测模型的可用性。

关键词: 离散元, 立式旋耕刀, 耕作阻力, 正交试验, 响应面