为了优化犁体曲面结构参数、减小铧式犁耕作阻力,采用水平直元线法设计犁体曲面,运用Solidworks软件建立实体模型,利用EDEM软件建立犁体—土壤离散元模型,并以犁体阻力最小为目标,对犁体铧刃角、犁铲安装角和导曲线扣垡角三因素进行正交仿真试验。仿真结果表明:所建立的犁体—土壤离散元模型可以较好地反映犁体在耕作过程中的阻力的变化情况,犁体阻力随着犁体与土壤接触面积的增大而增大,当犁体全部进入耕作状态时,犁体所受阻力达到2 621~2 795N,且趋于稳定。正交试验结果表明:铧刃角对犁体阻力影响极显著,犁铲安装角和导曲线扣垡角对犁体阻力影响显著。犁体结构最佳设计参数组合为:铧刃角45°,犁铲安装角25°,导曲线扣垡角5°,犁体阻力为2532 N,比优化前减少6. 36%。研究结果为犁体曲面优化设计提供一种离散元分析方法,也为犁体曲面的设计提供数据参考。
In order to optimize the structural parameters of the plow’s surface and reduce the working resistance of moldboard plow. In this paper,the method of horizontal straight line was used to design the plow surface and the Solidworks software was used to build the model. Meanwhile,the discrete element model of plough-soil was established by using EDEM software. And with the aim of minimizing the resistance of the plow,the orthogonal simulation test was carried out on the three factors those are the starting angle of straight-line element,the plow blade mounting angle and the buckle angle of guiding curve. The simulation results showed that the plough-soil discrete element model established in this paper can clearly reflect the change of plow’s resistance during the farming time. The resistance of the plow increased with the increase of the contact area between the plow and the soil. When the plow entered the farming state,the resistance of the plow reaches 2 621-2 795 N and tended to be stable. The orthogonal test showed that the influence of the starting angle of straight-line element on the plough resistance was extremely significant,and the plow blade mounting angle and the buckle angle of guiding curve had a significant influence on the resistance of the plough. The optimal design parameters of the plow’s structure were 45°of the starting angle of straight-line element,25°of the plow blade mounting angle,and 5°of the buckle angle of guiding curve. The plow resistance was 2 523 N,which was 6.36% lower than before optimization under this condition. The results provided an analysis method of discrete element for the design of the plow’s surface,and also provided data reference for the design of the plow.
Journal of Agricultural Mechanization Research