玉米大垄双行气力集排式追肥装置设计与试验

Design and Experiment of Pneumatic Centralized Fertilizer Application Device for Maize Large Ridge Double Row Planting

摘要:

针对玉米大垄双行种植模式下追肥作业效率低和排肥均匀性较差等问题，依据该种植模式下的追肥作业特点，设计一种适用于该种植模式的螺旋输送器排肥、多行集排、气流输肥的追肥装置，并对螺旋输送器式排肥装置和气力输送装置关键参数进行了理论计算和优化设计。依据排肥流量需求设计螺旋输送器叶片结构，并确定螺旋输送器驱动电机功率；确定气-肥输送主管道和气-肥输送分配管道结构尺寸；采用三通管将气-肥输送分配管道合并方式，使双苗带中间施肥量多于两侧。对该装置进行排肥试验，结果表明：螺旋输送器式排肥装置排肥稳定，排肥量与转速具有较好的线性相关性；设计二因素三水平排肥试验探究风速和排肥转速对肥料分配均匀性的影响，排肥转速、风速以及排肥转速与风速的交互作用均对各行排肥量一致性变异系数影响显著，各行排肥量一致性变异系数随着转速和风速的增大而增大；气-肥输送分配管道合并后，各行排肥量一致性变异系数略有增加，未合并出肥口各行排肥量一致性变异系数为6.5%~7.1%，合并出肥口各行排肥量一致性变异系数为3.8%~5.8%，合并出肥口排肥量为未合并出肥口排肥量的1.7倍左右，排肥性能达到设计目标，满足玉米追肥机械作业标准要求。

Abstract:

Aiming to address the issues of moisture absorption, low efficiency in topdressing operations, and poor uniformity in fertilizer distribution in the fertilizer top-dressing process for the large ridge double row planting mode of maize, a spiral conveyor fertilization device, multi row collection and airflow fertilization device suitable for this planting mode was designed based on the characteristics of fertilization operation. Theoretical calculations were conducted for the parameters of the spiral conveyor fertilizer discharging device and pneumatic conveying structure. The blade structure of the spiral conveyor was designed and the power of the spiral conveyor drive motor was determined according to the required fertilizer discharge rate. The structural dimensions of the main pneumatic fertilizer conveying pipeline and the pneumatic fertilizer distribution pipelines were determined. By merging the pneumatic fertilizer distribution pipelines using tee pipes, the fertilizer application rate in the middle of the double seedling rows was increased compared to the sides. Fertilizer discharging tests were conducted on this device, and the results showed that the spiral conveyor fertilizer discharging device provided stable fertilizer discharge, with the discharge rate linearly related to the rotational speed. A two-factor, three-level experiment was designed to investigate the effects of wind speed and fertilizer discharge rotational speed on fertilizer distribution uniformity. The rotational speed of fertilizer discharge, wind speed, and their interaction all had extremely significant effects on the coefficient of variation for uniformity in fertilizer discharge among rows. This coefficient was increased as both the rotational speed and wind speed increased. After merging the pneumatic fertilizer conveying pipes, the coefficient of variation for uniformity in fertilizer discharge among rows was slightly increased. The coefficient of variation for uniformity among rows without merged outlets ranged from 6.5% to 7.1%, while the coefficient with merged outlets ranged from 3.8% to 5.8%. The fertilizer discharge rate with merged outlets was approximately 1.7 times of that of the discharge rate without merged outlets. The fertilizer discharging performance met the design objectives and could effectively satisfy the mechanical operation standards for maize top-dressing.