谷子谷穗建模与仿真试验研究

谷子脱粒分离过程中籽粒运动与分布趋势直接影响清选负荷与质量,而脱粒分离过程观测与研究难度较大。为此,以龙谷31号谷子为研究对象,根据其谷穗结构、分枝情况,利用EDEM软件黏结模型建立了谷穗虚拟模型进行离散元仿真分析,并进行了仿真与台架的对比试验验证模型的准确性。试验结果表明:轴向脱出物籽粒分布符合BiDoseResp函数分布,周向脱出物籽粒分布符合GaussAmp函数分布,并分别求出轴向与周向对比试验拟合曲线方程,绘制拟合曲线,拟合结果均收敛。分别对两对拟合曲线进行差异性检验,结果表明:轴向与周向脱出物籽粒分布,仿真试验结果与台架试验结果差异性不显著,证明采用离散单元法分析谷子脱粒分离过程,其籽粒运动与分布规律与实际情况一致度较高,谷子脱粒分离过程可利用离散单元法进行深入研究与分析。

Modeling of Millet Ear and Experimental Study on Simulated Threshing Separation

The trend of grain movement and distribution in the process of threshing and separation has a direct impact on the cleaning load and quality,but it is difficult to observe and study the process of threshing and separation.Therefore,this paper takes Longgu No.31 millet as the research object.According to the structure and branches of the ear,the virtual model of the ear was established by using the binding model of EDEM software.The accuracy of the model is verified by simulation and bench test.The results showed that:the distribution of axial effluents was in accordance with BiDoseResp function,and that of circumferential effluents was in accordance with GaussAmp function.The fitting curve equations of axial and circumferential contrast tests are obtained respectively,and the fitting results are convergent.The results show that there is no significant difference between the simulation results and the bench test results.It is proved that the analysis of threshing and separating process of millet by discrete element method has a high consistency with the actual situation in grain movement and distribution.Discrete element method can be used to study and analyze the threshing and separation process of millet.