小麦小区育种脱粒装置优化设计与试验

Optimal Design and Test of Wheat Plot Breeding Threshing Device

摘要:

针对现有小麦小区育种脱粒机在多穗脱粒作业工况下籽粒破碎率与未脱净率高等问题，基于纹齿-刀齿组合式脱粒元件小区育种脱粒系统，本文开展脱粒元件结构设计与小麦脱粒分离接触力学分析。构建小麦柔性空心茎秆离散元模型，以籽粒未脱净率和破碎率为评价指标，探究脱粒元件前倾角、凸棱宽度和凸棱高度对小麦育种脱粒性能的影响。采用Box-Behnken分析方法构建小麦脱粒损失回归模型，确定纹齿-刀齿组合式脱粒元件最优结构参数为前斜角56°、凸棱宽度13.9mm和凸棱高度3.4mm。样机试验结果表明，当滚筒转速800r/min、喂入量15穗/次时，小麦籽粒未脱净率为0.71%，破碎率为0.14%，验证了设计的纹齿-刀齿组合式脱粒系统在小麦多穗育种脱粒作业工况下的有效性与优越性。

Abstract:

In order to solve the problem of high grain breakage rate and unthreshed grain rate of the existing wheat plot breeding threshing machine under the condition of multi-panicle threshing, a plot breeding and threshing system based on grain-tooth combined threshing element was proposed. Combined with the structure and working principle of the breeding threshing system, the contact mechanical analysis of wheat threshing separation and the structural design of threshing components were carried out. A discrete element model of flexible hollow stems of wheat was constructed, and the effects of the forward inclination angle, ridge width and ridge height of threshing component on the threshing performance of wheat breeding were explored by taking the unthreshed rate and breakage rate of grains as evaluation indexes. The Box-Behnken analysis method was used to construct a regression model of wheat threshing loss, and the optimal structural parameters of the grain-tooth combined threshing component were determined, with front bevel angle of 56°, ridge width of 13.9mm and ridge height of 3.4mm. The prototype trial production and test verification showed that when the drum speed was 800r/min and the feeding amount was 15 ears/time, the unthreshed grain rate of wheat grains was 0.71% and grain breakage rate was 0.14%. The effectiveness and superiority of the grain-tooth combined threshing system designed in wheat multi-panicle breeding and threshing operation were verified.