玉米根茬根土分离方式的试验研究

为确定较优的玉米根茬根土分离作业方式与作业参数,在根茎类作物根土分离试验台上进行了碾压、击打和抖动的单独及组合作业方式的根土分离效果对比试验。结果表明,采用碾压+击打组合方式对低含水率(10%~15%)的玉米根茬样品进行根土分离优于其他作业方式。为优化碾压+击打组合作业方式的作业参数,根据Box–Behnken试验设计原理,以根土分离率和作业功耗为性能指标,以轧距、飞锤转速和飞锤质量为试验因素进行试验,建立了根土分离率以及作业功耗的回归模型,通过响应曲面法分析指标与因素间的相互作用,并对回归模型进行多目标优化。优化获得的最佳作业参数为:轧距22 mm,飞锤转速200 r/min,飞锤质量0.3 kg,试验验证根土分离率为95.44%,作业功耗为0.72 k W,试验值与理论预测值基本一致,表明采用碾压+击打组合方式具有良好的根土分离效果。

Experimental study on corn stubble root-soil separation way

In order to achieve better operating type and optimal working parameters for the roots-soil separation, experiments under different working modes which include compacting, hitting, vibrating and the combination of above methods were performed by employing the test-bed of fibrous root crops. The experimental results showed that the better separation method can be obtained for the roots-soil complex with low moisture content by the combination of compacting and hitting method. Furthermore, experiments based on Box-Behnken experimental design method were performed for optimizing parameters. The roots-soil separation rate and power consumption were considered as the performance index, and the parameters including roll clearance, revolving speed of hammer, mass of hammer were selected as the independent parameters. The mathematical model corresponding to the roots-soil separation rate and power consumption was established. By the analysis of the interaction between the performance index and the independent parameters, multi-objective optimization for the mathematical model was obtained. The value of the optimal working parameters were as following: roll clearance of 22 mm, revolving speed of hammer of 200 r/min and mass of hammer of 0.3 kg, respectively. The roots-soil separation rate of 95.44% and power consumption of 0.72 kW were obtained by experiment, which were in accordance with the theoretical prediction. It was concluded that better separation rate could be obtained by employing the combination of compacting and hitting method.