Authors

Abstract

Aiming at the problems of high crushing rate and high non-threshing rate of maize grain direct harvesting under the condition of high water content and dense planting of single longitudinal axial flow machine widely used in southwest China, a tangential-horizontal axial flow double drum maize threshing device was designed and optimized. The combination mode of the drum was determined by theoretical analysis, and the influence of the vertical height between the two drums on threshing was studied. The flexible concave sieve and the transition sieve plate were redesigned. EDEM and Adams were used to simulate and analyze the threshing process to verify the rationality of the design. The prototype was built, and the drum speed, diversion angle and feeding amount were selected as the test factors. The response surface test was carried out with the crushing rate and the non-threshing rate as the test indexes. The multi-objective optimization of the regression model was carried out based on the response surface method. The combination of the optimal parameters after rounding was as follows : the drum speed was 453 r/min, the diversion angle was 69°, and the feeding amount was 6.7 kg/s. The verification test measured the maize crushing rate of 2.76% and the non-threshing rate of 0.11%, which met the production demand and could provide reference for the design of threshing device in southwest China.

Abstract in Chinese

针对西南地区普遍应用的单纵轴流机型在高含水率密植条件下玉米籽粒直收存在的破碎较高、未脱净率较高问题，设计切流-横轴流双滚筒玉米脱粒装置并进行优化设计，通过理论分析确定滚筒的组合方式，研究两滚筒间垂直高度对脱粒的影响，并对柔性凹板筛、过渡筛板进行重新设计，采用EDEM、Adams对脱粒过程进行仿真分析验证设计的合理性。搭建样机，选取滚筒转速、导流角、喂入量为试验因素，以破碎率和未脱净率为试验指标开展响应面试验，基于响应曲面法对回归模型进行多目标优化，得到最优参数圆整后的组合为：滚筒转速453r/min、导流角为69°、喂入量为6.7kg/s，验证试验测得玉米破碎率2.76%，未脱净率为0.11%，满足生产需求，可为西南地区的脱粒装置设计提供参考。