Abstract:

【Objective】 To study the physical characteristics of Apocynumapocynum and test the mechanical characteristics of stem in the hope of providing theoretical basis for the design of the Apocynum apocynum binder harvester. 【Methods】 The plant typecharacteristics and stem structure were observed and determined.Then the effects of stem diameter, phloem and loading speed on mechanical properties of Apocynum apocynum stem were studied by means of statistical data analysis. 【Results】 There was no yield stage in stem deformation during overwintering dormancy. The radial compressive load and radial compressive elastic modulus of the skinned and skinless stems first increased with the increase of diameter and then decreased slowly, and the skinned stems were larger than the skinless stems. The bending load and elastic modulus of stem increased and decreased with the increase of stem diameter. The shear load increased with the increase of stem diameter, and the shear energy consumption decreased and increased with the increase of loading speed and stem diameter, respectively. The influence of stem diameter on shear energy consumption decreases with the increase of loading speed. 【Conclusion】 It is necessary to consider the influence of stem structure, high cutting speed, tool front force, high hardness and high wear-resistant materials, cutting angle optimization and other design principles in the design and development of Apocynum apocynum binder harvester.

Key words: Apocynum apocynum L.; overwinter wilt period; mechanical properties; stem diameter; phloem; loading speed

摘要：

【目的】研究越冬休眠期罗布麻植株物理特征,进行茎秆力学特性试验,为罗布麻割捆收获机的设计提供理论依据。【方法】观察和测定罗布麻株型特征及茎秆结构,通过数据统计方法分析研究茎秆直径、韧皮和加载速度对罗布麻茎秆力学特性的影响规律。【结果】越冬休眠期罗布麻茎秆形变无屈服阶段;有皮、无皮茎秆的径向压缩载荷和径向压缩弹性模量先随着直径的增大先增加后缓慢减小,且有皮茎秆均大于无皮茎秆;茎秆弯曲载荷和弹性模量随着茎秆直径的增加而分别增加和减小;剪切载荷随着茎秆直径的增加而变大,剪切能耗随着加载速度和茎秆直径的增加分别减小和增加,且随着加载速度的增加,茎秆直径对剪切能耗的影响减弱。【结论】在设计与开发罗布麻割捆收获机械时,需考虑罗布麻茎秆结构的影响和切割速度高、刀具锋力、高硬度且高耐磨材料、切割角度优化等设计原则。

关键词: 罗布麻, 越冬休眠期, 力学特性, 茎秆直径, 韧皮, 加载速度