斜体式螺旋排肥系统设计与试验

Design and Experiment of Inclined Spiral Fertilizer Applicator and Fertilizer System

摘要:

针对传统变量施肥系统存在起步阶段化肥颗粒输送时间长，产生施肥空白区进而影响施肥量精度的问题，设计了斜体式螺旋排肥系统，包括斜体螺旋排肥器、步进电机、驱动器、人机交互屏、单片机、编码器测速模块、矩阵光线传感器等；理论分析了颗粒运移受力过程，采用EDEM模拟了排肥均匀性及肥料颗粒在加速排肥和未加速排肥条件下的运动过程，得出所设计排肥器排肥连续均匀，无断点排肥现象。同时加速排肥条件下化肥颗粒排出速度由0.017m/s提高至0.162m/s，垂直方向上的分速度由0.005m/s提高至0.057m/s，化肥可快速运移排出，避免了排肥器与排肥管接口部位的阻挡，提高了排肥稳定性。进行了台架试验，结果表明加速排肥条件下的滞后距离随着作业速度增大而增大，未加速排肥的滞后距离与作业速度无明显关系；加速排肥条件下存在实际排肥量超过理论排肥量现象，但仍低于未加速排肥所导致的排肥波动量。进行了田间试验，结果显示未加速排肥时的平均施肥滞后距离为1.06m，施肥精度77.6%；加速排肥条件下，平均施肥滞后距离为0.40m，施肥精度提高至96.5%。排肥系统可以明显缩短施肥滞后距离，提高施肥精度。

Abstract:

In view of the long transportation time of chemical fertilizer particles during the fertilizer discharge operation of the spiral fertilizer discharger, which led to the problem that the lag distance of fertilization in the initial stage of fertilization operation affected the accuracy of fertilization amount, an inclined spiral fertilizer discharger was designed, and the movement time of chemical fertilizer in the fertilizer discharger through the accelerate fertilizer fertilizer measure of the fertilizer discharger was reduced, and the lag distance of fertilization to improve the accuracy of fertilization was shortened. EDEM was used to simulate the movement of fertilizer particles in the fertilizer discharger under the conditions of accelerate fertilizer and unfilled fertilizer. Under the condition that the oblique angle of the fertilizer discharger and the maximum speed was 191.74r/min, the full speed of the fertilizer particles was increased from 0.017m/s to 0.162m/s, and the vertical velocity was increased from 0.005m/s to 0.057m/s, which increased the speed of the fertilizer particles leaving the fertilizer discharger and shortened the transportation time of fertilizer particles by 3.199s. The bench test was carried out. The test results showed that pre-filling fertilizer could significantly shorten the lag distance of fertilization, but the lag distance under pre-filling fertilizer was increased with the increase of operation speed. The lag distance of unprefilled fertilizer was increased with the increase of fertilizer application rate, but it had no obvious relationship with the operation speed. The amount of fertilizer applied under the condition of accelerate fertilizer was higher than that without accelerate fertilizer, which increased the accuracy of fertilization, but there was an overshoot of fertilizer application, which can be solved by further optimization. The field experiment was carried out by modifying the seeder. The field experiment results showed that the average lag distance of fertilization was 1.06m when the pre-filling fertilizer was not pre-filled, and the average lag distance of pre-filling fertilizer was 0.40m, which was shortened by 0.66m. The precision of fertilization control was improved from 77.6% to 96.5%.