关键词: 土壤模型, 旋耕刀, 离散元, 多体动力学, 微耕机

Abstract: Rotary tillage components are the core components of the power tiller, and their quality directly affects the tillage efficiency and work quality of the tiller. The typical rotary cutter shaft and purple soil in Chongqing were taken as the research objects. Based on the discrete element method (DEM) and multi-body dynamics (MBD) theory, the nonlinear visco-elastic plastic contact model (edinburgh elasto-plastic adhesion model, EEPA) was used to analyze the knife roller farming process on the EDEM and Recurdyn software platform under the condition of the forward speed 0.2 m·s^-1, the rotary speed 110 r·min^-1 and the tilling depth 150 or 200 mm. At the same time, the equivalent torque of the cutter shaft was tested on the soil-bin test bed in laboratory developed by our team. The results showed that the torque variation rules of different tool holders on the same cutter shaft were similar, but the values were not consistent. The equivalent torque of the cutter shaft was not simply equal to the torque of a single tool holder timed the number of tool holders. Furthermore, the variation law of the equivalent torque of the cutter shaft was same under different tillage conditions, and the maximum relative error between the simulation results and the experiment results with the tilling depth of 150 and 200 mm were 14.01% and 11.49%, respectively. The  results provided the reference for discussion between rotary blades and soil, as well as optimization of the tilling performance of the tiller.

Key words: soil models, rotary blades, DEM, MBD, power tiller