离心甩肥式种肥精准穴施装置设计与试验

Design and Experiment of Centrifugal Ejection-type Device for Placement of Starter Fertilizer in Planting Holes

摘要:

玉米种肥穴施是提高肥料利用率的有效途径,针对高速作业时穴施肥装置成穴性差、施肥量不稳定等问题,提出了离心甩肥式玉米穴施肥方法,并设计了穴施肥装置。分析了影响穴施肥装置成穴性能的主要因素,确定了排肥勺转速、每穴施肥量对成穴性能的影响规律;以排肥勺转速、推肥段角度、引流板形状、每穴施肥量为试验因素,以肥料初始速度、肥团初始长度、穴径长轴长度为评价指标,采用离散元仿真方法进行了单因素试验,确定了推肥段角度为120°,引流板形状为正弦曲线。台架试验结果表明,播种机作业速度3~12 km/h时,肥料穴径长轴长度20.8~23.6 mm,成穴性良好;设计了玉米播种同步穴施肥控制算法,以STM32F103C8T6为核心完成了控制系统硬件和软件的设计,实时检测计算并控制种肥相对位置。田间试验表明,在作业速度1.5~9.0 km/h、施肥量3~6 g/株条件下,肥料平均穴径长轴长度为49.7~102.3 mm,变异系数为0.58%~4.39%,种肥平均间距为35.7~42.3 mm,合格率达92%以上。

Abstract:

Aiming to address issues such as poor hill-forming performance and unstable fertilizer application rates in high-speed operations, a centrifugal swing-type corn hill-drop fertilization method was proposed, and a corresponding hill-drop fertilization device was designed. The main factors affecting the hill-forming performance of the device were analyzed, and the influence patterns of the rotational speed of the fertilizer discharge scoop and the fertilizer application rate per hill on hill-forming performance were determined. Single-factor experiments were conducted by using the discrete element simulation method, with the rotational speed of the fertilizer discharge scoop, scoop head angle, shape and size of the deflector plate, and fertilizer application rate per hill as test factors, and the initial velocity of the fertilizer, initial length of the fertilizer cluster, and long axis of the fertilizer hill diameter as evaluation indicators. The results determined that the scoop head angle should be 120°, and the deflector plate shape should be sinusoidal. Bench tests showed that when the planter operating speed ranged from 3 km/h to 12 km/h, the long axis of the fertilizer hill diameter ranged from 20.8 mm to 23.6 mm, indicating good hill-forming performance. A control algorithm for synchronizing corn sowing and hill-drop fertilization was designed, with the STM32F103C8T6 as the core, completing the hardware and software design of the control system. This system detected, calculated, and controlled the relative position of seeds and fertilizers in real time, ensuring precise matching. Field experiments demonstrated that at operating speeds of 1.5 km/h to 9.0 km/h and fertilizer application rates of 3 g/plant to 6 g/plant, the average long axis of the fertilizer hill diameter ranged from 49.7 mm to 102.3 mm, with a coefficient of variation of 0.58% to 4.39%, and the average spacing between seeds and fertilizers ranged from 35.7 mm to 42.3 mm, meeting the operational requirements for precise corn hill-drop fertilization.