【摘要】 采用离散元法从微观角度剖析玉米子粒在脱粒过程中运动状态,建立切流-横轴流玉米脱粒装置离散元分析模型,利用EDEM软件仿真柱齿-板齿横轴流滚筒对玉米子粒在脱粒装置中轴向质量分布的影响,并将台架试验结果与仿真试验结果进行t检验分析。结果表明,两者相关系数为0. 491,修正后相关系数为0. 865,两者在轴向质量分布变化趋势一致,且没有显著差异,验证了离散元仿真玉米脱粒过程的可靠性和有效性。分析了单个玉米子粒物料在脱粒滚筒运动过程中在X、Y、Z 3个方向距离和受力变化。分析结果表明,子粒在X方向的最大瞬时速度为9. 964 m·s^-1和-11. 947 m·s^-1,在Y方向的最大瞬时速度为13. 051 m·s^-1和-6. 104m·s^-1,在X正向上最大受力为18. 7 N,在Y负向上最大受力为92. 5 N,Z轴在正、负方向上都有受力,最大正向受力为22. 0 N,说明柱齿-板齿滚筒在脱粒过程中可以在X、Y正负向都提供打击力,并在Z向推动玉米子粒前进,由于挡板作用,子粒在B区运动受到阻碍,有利于玉米完全脱粒及快速排出避免破碎。更多还原

【Abstract】 The discrete element method was used to analyze the movement state of corn kernels in the threshing process from a microscopic perspective. A discrete element analysis model for corn threshing device with shear-cross-axial flow was established,and EDEM software was used to simulate the axial mass distribution of corn kernel in the threshing device by column-toothed-plate-tooth drum. In addition,the bench experiment result and simulation experiment result were analyzed by variance. The results showed that,the correlation coefficient was 0. 491 and the corrected correlation coefficient was0. 865. There was no significant difference between the simulation experiment and bench experiment of axial mass distribution curves of corn kernel. The reliability and validity of discrete element simulation of corn threshing process were verified. Then,the distance and stress change of single corn kernel in the direction of X,Y and Z during the threshing drum movement were analyzed. The results of analysis indicate that,the maximum instantaneous velocity of corn kernel was 9. 964 m·s^-1 and-11. 947 m·s^-1 in the X direction,and 13. 051 m·s^-1 and-6. 104 m·s^-1 in the Y direction. The maximum force in positive X was 18. 7 N,in negative Y was 92. 5 N. The Z-axis has forces in both positive and negative directions,the maximum positive force was 22. 0 N,which illustrated that the cylinder of columnplate-tooth horizontal axis flow could provide striking force in both positive and negative directions of X and Y,and pushed forward corn seeds in Z direction. Due to the role of baffle,the movement of corn seeds in Region B is hindered,which was conducive to complete threshing and rapid discharge of corn kernel in Region B to avoid crushing.更多还原