紫云英种子力学性能与脱粒碰撞损伤机理研究  

Research on mechanical properties and threshing-impact damage of Astragalus sinicus seeds

作　　者：曹明珠 高学梅 王建楠 游兆延 吴惠昌 王公仆 Cao Mingzhu;Gao Xuemei;Wang Jiannan;You Zhaoyang;Wu Huichang;Wang Gongpu(Nanjing Institute of Agricultural Mechanization,Ministry of Agriculture and Rural Affairs,Nanjing,210014,China)

机构地区：[1]农业农村部南京农业机械化研究所,南京市210014

出　　处：《中国农机化学报》2022年第5期77-84,共8页Journal of Chinese Agricultural Mechanization

基　　金：中国农业科学院所级基本科研业务费专项(S202012—03);现代农业产业技术体系(CARS—22)。

摘　　要：针对中国紫云英机械化收获技术起步较晚、缺乏专用机收装备,现有改装紫云英收获装备作业性能不够稳定、关键部件缺乏理论支撑等现状。应用Herts理论,从接触碰撞角度,推导收获期紫云英脱粒作业中籽粒挤压变形量和最大应力分布函数,建立籽粒与脱粒钉齿接触碰撞相对速度模型,进行紫云英种子的表面挤压力学性能测试和全喂入脱粒碰撞损伤试验,探寻紫云英脱粒产生碰撞损伤时籽粒与脱粒钉齿临界相对速度,深入分析紫云英脱粒损伤机理,获取种子脱净率和破损率指标随脱粒钉齿线速度变化曲线。理论研究结合试验验证表明,全喂入紫云英机脱粒作业过程中,籽粒发生碰撞损伤时籽粒与脱粒钉齿的临界相对速度为27.31 m/s;在紫云英收获实际作业中控制脱粒钉齿线速度在25 m/s附近时,紫云英收获脱净率和破损率两项指标组合达到最优,脱粒指标脱净率大于99.5%,破损率低于0.33%。相关研究结果为进一步深入探索紫云英收获损伤机理和脱粒装置的优化设计提供理论依据。Astragalus sinicus(Chinese milk-vetch) is one of the main rotation crops in rice field in the south of China,and also an important forage or green manure crop.During the fall-winter season and land fallow period,planting green manure could increase content of soil organic matter.This improves soil fertility and renews soil production.It plays a vital role not only in the sustainable development of agriculture,crop industry and grain quantitative safety,but also the sustainable development of environment,food qualitative safety and human health.In recent years,with the rapid growth of Astragalus sinicus planting area in China,Astragalus sinicus harvesting mechanization technology and equipment requirement have increased rapidly.The research on Astragalus sinicus mechanized harvesting technology appeared relatively late in China.Naturally,the refitted Astragalus sinicus harvesters from rice combine harvesters were used.The refitted Astragalus sinicus harvesters have inadequate stable performance due to the lack of special harvesters.Limited design of the key components also lacked supporting essential theory.The previous researches on mechanical properties and collision mechanism of grain seeds have mostly focused on big crop seeds,but Astragalus sinicus seeds have been rarely studied.In this research,from Contact-impact view,the surface compression mechanical properties of Astragalus sinicus seeds were measured,and the analysis on collision mechanism was explored during full-feeding Astragalus sinicus threshing.The study found that the central deformation increased linearly with the increase of the pressure load.The central deformation changed a little slower under low pressure load.The distribution function of the maximum stress and the central deformation were derived during Astragalus sinicus threshing process.In the early stages of collision,the maximum stress of Astragalus sinicus seeds increased sharply when the central deformation increased.On the contrary the maximum stress changed gradually in the late st

关 键 词：紫云英 力学性能 脱粒 碰撞 损伤 

分 类 号：S551[农业科学—作物学] S220.1