弧槽双螺旋式排肥器优化设计与试验

为实现排肥器的精量排肥,对采用错位叠加单螺旋排肥曲线原理的弧槽双螺旋式排肥器的排肥性能进行理论分析,确定其排肥量及影响其排肥性能的因素,以螺距S、弧槽半径Rp、中心距a为试验因素,并以均匀性变异系数、施肥精度为试验指标,进行了三因素三水平Box-Behnken试验,得到最优参数：螺距S为35mm,弧槽半径Rp为17.5mm,中心距a为35mm,在最优参数组合下制作排肥器并进行台架验证试验与对比试验,试验结果表明：台架试验的均匀性变异系数、施肥精度与仿真试验相对误差分别为5.07%、4.69%,仿真与台架试验吻合度较好,对比试验结果表明：优化后弧槽双螺旋式排肥器施肥精度为3.35%,施肥精度较高,优化后弧槽双螺旋式排肥器较未优化弧槽双螺旋式排肥器、单螺旋排肥器均匀性变异系数分别降低7.26、15.48个百分点,优化后的弧槽双螺旋式排肥器排肥性能良好。

Optimal Design and Experiment of Arc-groove Double-spiral Fertilizer Discharge Device

Precision fertilization is a high-efficiency fertilization method, and the fertilizer ejector is a key link in precision fertilization. In order to realize the precise fertilizer discharge of the fertilizer ejector, the fertilizer discharge performance of the arc-groove double-screw fertilizer discharge device based on the principle of dislocation superposition single screw fertilizer discharge curve was analyzed, the factors affecting its fertilizer discharge performance were obtained, and the factors affecting the fertilizer discharge uniformity of the arc-groove double-spiral fertilizer discharge device were obtained, taking the pitch S, arc-groove radius Rp and center distance a as the test factors, and taking the uniformity variation coefficient and fertilization accuracy as the test indexes, the three-factor and three-level Box-Behnken test was carried out. The optimal parameters were pitch S=35mm, arc-groove radius Rp=17.5mm and center distance a=35mm. The arc-groove double-spiral fertilizer discharge device was made under the optimal parameter combination, and the bench verification test and comparative test were carried out. The test results showed that the uniformity variation coefficient of bench test and the relative error between fertilization accuracy and simulation test were 5.07% and 4.69%, respectively, and there was little difference between them, which verified the correctness of simulation. The uniformity variation coefficient of the optimized arc-groove double-spiral fertilizer discharge device was 7.26 and 15.48 percentage points lower than that of the non optimized arc-groove double-spiral fertilizer discharge device and single spiral fertilizer discharge device respectively. The optimized arc-groove double-spiral fertilizer discharge device had good fertilizer uniformity and effectively solved the problem of uneven fertilizer discharge of the single helix fertilizer ejector, it can provide a reference for the structural improvement and optimization of arc-groove double spiral fertilizer ejector.