基于DEM-MBD的铲链式花生收获机设计与试验

Design and Experiment of Shovel Chain Peanut Harvester Based on DEM-MBD

摘要:

针对花生挖掘收获过程中土块分离效率低、落果损失率高等问题,设计了一种铲链式花生收获机。通过对花生植株和土壤颗粒受力情况开展分析,探究了花生植株土壤复合体在输送去土、翻转放铺过程中的运动规律,并对输送分离装置和翻转铺放装置等结构参数进行了优化设计。基于DEM-MBD 耦合方法建立了花生植株土壤回环输送链仿真模型,并开展花生植株输送去土过程仿真试验,探究了回环输送链速度、回环输送链倾角、振动轮转速对花生植株受力情况的影响规律。开展了花生挖掘收获田间试验,以含土率和落果率为试验指标,求解最优参数组合。田间试验表明:回环输送链速度1. 5 m/ s、回环输送链倾角25°、振动轮转速150 r/ min 时,花生落果率为 2. 9% ,花生含土率为6. 4% ,各项性能指标均满足相关标准的规定。

Abstract:

Aiming to address the issues of low separation efficiency of soil blocks and high loss rate of fallen fruits during peanut harvesting, a shovel-chain type peanut harvester was designed. Through analysis of the force conditions on peanut plants and soil particles, the motion laws of the peanut plant-soil composite body during the process of transportation without soil, flipping and laying were explored. The structural parameters of the transportation separation device and the flipping and laying device were optimized. Based on the DEM-MBD coupling method, a simulation model of the peanut plant-soil-loop transportation chain was established, and simulation experiments on the peanut plant transportation without soil were carried out to explore the influence laws of the loop transportation chain speed, loop transportation chain inclination angle, and vibration wheel speed on the force conditions of the peanut plants. Field experiments for peanut digging and harvesting were conducted, with the inclusion rate of soil and loss rate of fallen fruits as test indicators. The optimal parameter combination was solved. The field experiments showed that when the loop transportation chain speed was 1. 5 m/ s, the loop transportation chain inclination angle was 25°, and the vibration wheel speed was 150 r/ min, the loss rate of fallen peanuts was 2. 9% , the inclusion rate of peanuts was 6. 4% , and all performance indicators met the requirements of relevant standards.