基于离散元法立式螺旋开沟器开沟质量的评价

为了定量评价立式螺旋开沟器的开沟质量,构建立式螺旋开沟器与土壤相互作用的三维离散元模型,土壤颗粒之间选用Hertz-Mindlin with Bonding模型,以转速180 r/min、前进速度0.027 m/s模拟开沟1.88 m,利用EDEM软件Analyst模块中的标尺、查询等工具对开沟质量指标进行定量测定,结果表明沟型整齐,平均开沟宽度29.4 cm,平均开沟深度31.7 cm,开沟深度稳定性为87.32%,沟底浮土6.924 kg/m,直观给出沟两侧抛土量的分布图.开沟质量符合《田间开沟机械作业质量》(NY/T 740-2003)的要求,为立式螺旋开沟器的参数优化奠定了基础.

Estimation of the Operation Quality of Vertical Helix Furrow Openers Based on the Discrete Element Method

In order to evaluate the operation quality of vertical helix furrow openers (ditchers) quantitatively, a discrete element model was built to simulate the interaction between the vertical helix furrow opener and the soil. The Hertz-Mindlin with Bonding contact model was selected to calculate the contact force between soil particles. The ditching process was simulated by setting the rotation speed of the furrow opener at 180 r/min and the forward speed at 0.027 m/s, and ditching a furrow 1.88 m in length. The operation quality indexes were measured by using the Ruler and Queries Tools, which can be found in the EDEM software Analyst module. The results showed that the average ditching width was 29.4 cm, the average ditching depth was 31.7 cm, the stability coefficient of the ditching depth was 87.32% and the mass of loose soil in the furrow bottom was 6.924 kg/m, all of which met the requirements of the national standard Field Operation Quality of Ditchers (NY/T 740-2003).