Abstract: Grain crushing technology is the key technology to improve the quality of silage corn feed, and it is also the bottleneck of restricting silage corn feed mechanization devices. In this paper, SW threedimensional modeling, discrete element method, and field experiment were combined to explore the whole plant corn discrete element model, to simulate the process of crushing roller and corn straw, corn grain mutual operation in the process of grain crushing operation. The mechanical analysis of the crushing roller was carried out, and the whole plant corn adhesive contact model was used to simulate the crushing process between the rollers. Finally, the field experiment was carried out to verify the authenticity of the simulation results. In order to improve the efficiency of the crushing device and further optimize its structure, the effects of different working parameters on the operation quality and crushing rate of silage corn grain crushing device were studied. The results showed that: in the compression and shear test of corn straw, corncob, and grain, when the loading speed was 4 mm/min, and the roller gap was 2 mm, the maximum critical rupture loads of corn stalks and corn cobs under axial compression were approximately 2 360 N, corn kernel was approximately 48 N, the maximum radial critical shear forces of corn stalks and corn cobs were 625 N and 840 N, respectively, corn kernel was 23 N, and the crushing rate reached a maximum of 96%. The simulation results are consistent with the experimental results, which shows that the threedimensional discrete element model established in this paper can be applied. It is used to simulate the crushing process of silage corn grain crushing device, and the test results meet the quality requirements of corn grain crushing, which provides a theoretical basis and technical support for further study of grain crushing mechanism and analysis of influencing factors of grain crushing.

Key words:  silage corn, grain crushing device, counterroller, EDEM, discrete element method

摘要： 籽粒破碎技术是提高青贮玉米饲料品质的关键技术,也是制约青贮玉米饲料机械化装置的瓶颈。采用SW三维建模、离散元法和田间试验相结合的方法,探究全株玉米离散元模型,模拟籽粒破碎作业过程中破碎对辊与玉米秸秆、玉米籽粒相互作业的过程;并对破碎对辊进行力学分析,用全株玉米粘结接触模型对对辊间破碎过程进行仿真试验,最后通过田间试验验证仿真结果的真实性。旨在研究青贮玉米籽粒破碎装置中不同工作参数对其运行质量及籽粒破碎率的影响,提高破碎装置的效率,进一步优化其结构。结果表明:在秸秆、玉米芯及籽粒的压缩和剪切试验中,设定加载速度为4 mm/min,对辊间隙为2 mm时,玉米秸秆和玉米芯轴向压缩最大临界破裂载荷均近似为2 360 N,玉米籽粒则近似为48 N,玉米秸秆和玉米芯径向最大临界剪切力分别为625 N和840 N,玉米籽粒则为23 N,破碎率达到最大值96%,仿真结果与试验结果保持一致,表明本文建立的三维离散元模型可应用于仿真青贮玉米籽粒破碎装置工作过程中的破碎情况,试验结果满足玉米籽粒破碎质量要求,为进一步研究籽粒破碎机理,分析籽粒破碎的影响因素提供理论依据和技术支持。

关键词: 青贮玉米, 籽粒破碎装置, 对辊, EDEM, 离散元法