大豆联合收获机田间清选作业参数优化

为了改变国内大豆联合收获机田间作业时因清选装置的参数调节缺乏相应理论指导,造成清选参数调控不及时与不精确而导致大豆机收清选损失率和含杂率均较高的现状,该研究利用多参数可调可测式清选系统进行了大豆机收清选参数优化田间试验,分析了大豆机收时清选参数(作业速度、鱼鳞筛筛片开度、风门开度、风机转速和振动筛曲柄转速)对清选指标(清选损失率和含杂率)的影响规律,求解出最佳清选参数组合,完成大豆机收最佳清选参数组合的田间验证试验。试验结果表明,清选参数对清选损失率影响大小排序为振动筛曲柄转速、风机转速、作业速度、风门开度、鱼鳞筛筛片开度,清选参数对含杂率影响大小排序为鱼鳞筛筛片开度、风门开度、风机转速、作业速度、振动筛曲柄转速。求解出清选损失率偏小和含杂率偏小且喂入量偏大时最佳清选参数组合为作业速度6 km/h、鱼鳞筛筛片开度32 mm、风门开度17°、风机转速1 310 r/min和振动筛曲柄转速410 r/min,此时清选损失率为0.25%,含杂率为0.61%,与模型优化值的相对误差分别是0.250%和0.113%,对比常用清选参数条件下大豆联合收获机田间试验的清选指标,清选损失率下降了0.05%,含杂率下降了2.09%。研究结果可为大豆联合收获机田间作业时清选参数的设定与调控以及自适应清选系统调控策略的研发提供理论依据。

Optimization of field cleaning parameters of soybean combine harvester

At present, there are few studies on the influence of the cleaning parameters of soybean harvester on the cleaning indexes in China. In order to change the current situation of soybean combine harvester, due to the lack of theoretical guidance for the parameter adjustment of the corresponding cleaning device, the cleaning parameter adjustment is not timely and accurate, resulting in high loss rate and high impurity content of soybean harvester. In this study, the multi parameter adjustable and measurable cleaning system was used to optimize the cleaning parameters of soybean harvester in field test. The influence rules of the five cleaning parameters on the two cleaning indexes were analyzed, and the best cleaning parameter combination was found. The field verification test of the best cleaning parameter combination of soybean harvester was completed. Based on the analysis of the structure of cleaning system and the principle of cleaning operation of soybean harvester, the importance of the operating parameters and operating speed of cleaning device to the cleaning indexes of soybean combine harvester was obtained. The operation speed, opening of chaffer screen, damper opening, fan speed and crank speed of shale shaker were used to optimize the five cleaning parameters in field experiments. Cleaning loss rate and impurity rate were used to optimize the two cleaning indexes of field experiments. Through the analysis of the influence of cleaning device on the indexes of soybean combine harvester, the cleaning loss rate and impurity rate were determined as cleaning indexes, and in the field experiment, the cleaning loss of samples were collected in the form of binding cleaning loss receiving bag at the back of cleaning room to optimize the parameters of cleaning loss in the field experiment. Response surface test design and data analysis are completed by using design expert software. The contribution rate and response effect of each parameter on the two cleaning indexes were analyzed by the contribution rate method and response surface diagram. The results showed that the order of influence of cleaning parameters on cleaning loss rate was crank speed of shale shaker, fan speed, operation speed, damper opening, opening of chaffer screen. The order of influence of cleaning parameters on the impurity rate was opening of chaffer screen, damper opening, fan speed, operation speed, crank speed of shale shaker; The results showed that when the cleaning loss rate was small and the impurity rate is small and the feeding amount is large, the optimal cleaning parameters were operation speed 6 km/h, opening of chaffer screen 32 mm, damper opening 17°, fan speed 1 310 r/min and crank speed of shale shaker 410 r/min. At this time, the cleaning loss rate is 0.25%, the impurity rate is 0.61%, and the relative error with the optimized value of the model is 0.250% and 0.113%, respectively. Compared with the cleaning indexes of the field experiment of soybean combine harvester under the common cleaning parameters, the cleaning loss rate is reduced by 0.05%, and the impurity rate is reduced by 2.09%. The results provide a theoretical basis for the setting and adjustment of cleaning parameters and the research and development of self-adaptive cleaning system.