水稻秸秆不同部位剪切性能分析

剪切性能对于水稻收割和稻秸再利用至关重要。为获取水稻秸秆力学特征参数，针对不同部位稻秸的剪切性能进行试验研究，设计并制备不同稻秸直径相适应的剪切夹具，分别对稻秸的上、中、下和节部取样，考察了20、50、100、150、200和250 mm/min剪切速度对剪切力的影响。结果表明，自制夹具可胜任剪切测试任务，稻秸取样部位和剪切速度对剪切力有极显著影响。对于剪切部位而言，稻秸根部的剪切力大于上部；对于剪切速度而言，较高剪切速度（200～250 mm/min）下的剪切力小于低速剪切（20～50 mm/min），但与中速剪切（100～150 mm/min）相差较小。本研究结果可为稻秸收割机及稻秸粉碎机中剪切部件的设计与制造提供理论和试验数据支持。 

Experiment and Analysis of Shearing Property of Rice Straws

To obtain mechanical characteristic parameters of rice straws，shearing properties of rice straws from different part were investigated.Influence of sampling part（top，middle，bottom and joint）and shearing velocity（20，50，100，150，200 and 250 mm/min）on shearing force of rice straws was studied.Results showed that sampling height and shearing velocity revealed significant impact on shearing force，respectively.Shearing force increased with sampling section from top to bottom.Shearing force obtained by higher shearing velocity was less than the lower one.Meanwhile，no significant difference between shearing force of higher and middle shearing velocity.As a result，it is advisable to take medium shearing velocity.Result of this study can provide theoretical and experimental data support for design and manufacture of shear parts in rice straw harvester and rice straw crusher.