玉米籽粒收获机清选装置参数优化试验

针对玉米籽粒直收过程中清选作业损失率高、籽粒含杂率高的问题,开展玉米籽粒收获机清选作业参数优化试验,探究整机作业工况下清选装置作业参数对籽粒损失率和含杂率的影响规律,得到清选作业参数最优组合,并进行田间验证试验。玉米籽粒收获机清选作业参数较优水平区间为风机转速800～1 000 r/min,振动频率6～8 Hz,上清选筛筛孔开度15～25 mm。清选作业籽粒含杂率最优作业参数组合为风机转速1 000 r/min,振动频率7 Hz,上清选筛筛孔开度20 mm;籽粒损失率最优作业参数组合为风机转速900 r/min,振动频率6 Hz,上清选筛筛孔开度20 mm;清选作业综合指标最优作业参数组合为风机转速900 r/min,振动频率7 Hz,上清选筛筛孔开度20 mm。得到玉米籽粒收获机清选作业籽粒含杂率、籽粒损失率和综合指标的回归模型,田间验证试验表明,籽粒含杂率相对误差为5. 56%,籽粒损失率相对误差为5. 10%,综合指标相对误差为4. 60%,最优作业参数组合表现良好,且回归模型可靠。

Optimization Experiment on Cleaning Device Parameters of Corn Kernel Harvester

Cleaning is one of the most important working processes of corn kernel harvester. However, high loss and high impurity seriously restrict the effect of cleaning process. The impurity rate and loss rate were directly affected by working parameters of cleaning devices. So working parameters optimization experiment of cleaning devices was carried out by using corn kernel harvester. Fan speed, vibration frequency and opening degree of upper screen were selected as experiment factors. The better levels of three experiment factors were obtained by single factor experiment. The better levels of fan speed were ranged from 800r/min to 1000r/min. The better levels of vibration frequency were ranged from 6Hz to 8Hz. The better levels of opening degree of upper screen was ranged from 15mm to 25mm. Based on single factor experiment results, the optimal combination of three test factors and regression model were obtained by orthogonal experiment. The optimal factor combination of cleaning impurity rate was fan speed of 1000r/min, vibration frequency of 7Hz, and opening degree of upper screen of 20mm. The optimal factors combination of cleaning loss rate was fan speed of 900r/min, vibration frequency of 6Hz, and opening degree of upper screen of 20mm. The optimal factor combination of cleaning comprehensive weighted index was fan speed of 900r/min, vibration frequency of 7Hz, and opening degree of upper screen of 20mm. Three regression models were verified by field test. The relative error of regression model of cleaning impurity rate was 5.56%. The relative error of regression model of cleaning loss rate was 5.10%. The relative error of regression model of cleaning comprehensive weighted index was 4.60%. The results showed that three regression models were reliable.