固体有机肥破碎条施机设计与试验

针对发酵厩肥长期堆放过程中易结块，肥料破碎条施困难等问题，该研究提出了螺旋桨叶与差速对辊组合的固体有机肥破碎条施机，以解决传统链排式运肥装置作业过程中肥料结块架空、条施排肥困难、施肥不均匀等问题。将Hertz-Mindlin with bonding和Hertz-Mindlin with JKR模型结合建立结块和散体肥料共同组成的固体有机肥离散元模型，并以肥料颗粒质量变化、螺旋桨叶扭矩，有机肥颗粒受力和平均运动速度为评价指标对桨叶的运肥和碎肥过程进行分析，明确参数变化对肥料运动的影响；进行桨叶和肥箱受力分析，探明运肥和碎肥过程中的应力分布情况；对开沟施肥铲和镇压轮的工作过程进行分析，明晰开沟深度、铲尖倾角、镇压倾角对开沟和镇压过程的影响。离散元仿真分析结果表明，碎肥过程肥箱内的桨叶平均扭矩为52.05 N·m 和58.75 N·m，有机肥颗粒平均受力为343.25和374.38 N，远高于运肥过程的平均扭矩20.42 N·m 和有机肥颗粒平均受力224.22 N；其中，运肥和碎肥过程中有机肥颗粒运动速度稳定在0.6 m/s左右，肥箱内有机肥颗粒质量变化稳定，无明显波动；螺旋桨叶和肥箱受力较大的区域主要集中在桨叶齿爪和肥箱的底部与侧壁。基于上述分析结果，对固体有机肥破碎条施机开展样机试制并进行田间试验，结果表明，9 组作业参数组合下施肥量变异系数平均值为21.5%，条施机最优工作参数组合为：镇压倾角120°，前进速度5 km/h，开沟施肥深度150 mm，此时施肥量变异系数为15.2%，施肥过程稳定可靠。研究结果可为东北黑土区耕地保护和固体有机肥破碎条施提供装备支撑。

Design and experiment of solid organic fertilizer crushing and striping machines

Because of the problems of easy caking of fermented manure during long-term stacking and the difficulty of fertilizer crushing and striping, a solid organic fertilizer crushing and striping method combined with propeller blades and differential roller was proposed to solve the problems such as fertilizer caking and overhead fertilizer boxes, difficulty in strip application, and uneven fertilization amount during the operation of traditional chain-type fertilizer transport devices. Hertz-Mindlin with bonding and Hertz-Mindlin with JKR models were combined to establish the discrete element model of solid organic fertilizer composed of caked and bulk fertilizers. The process of fertilizer transport and fertilizer crushing of the paddle was studied with the quality change of fertilizer particles, the torque of propeller blades, the force of organic fertilizer particles, and the average movement speed as evaluation indicators. The stress distribution of the blade and the fertilizer box during transporting and crushing fertilizer was investigated by force analysis, the working process of the trenching fertilizer shovel and the compaction wheel was analyzed, and the influence of the change of the shovel tip angle and the compaction angle on the soil resistance during the trenching and compaction process was clarified. The discrete element simulation analysis results shown that the average torque of the crushing stage in fertilizer crushing was 52.05 and 58.75 N·m, the average force of particles was 343.25 and 374.38 N,wich were much higher than the average torque of transport fertilizer stage in fertilizer transportation(20.42 N·m and 224.22 N). The movement speed of organic fertilizer particles was stable at about 0.6m/s in the process of fertilizer transportation and fertilizer crushing, and the particle mass was stable without apparent fluctuation. The area with significant force position was mainly concentrated at the bottom and side wall of the blade and fertilizer box. Based on the above analysis results, a solid organic fertilizer crushing and striping machine was developed, and field experiments were conducted. The results showed that the average coefficient of variation of fertilization amount under 9 sets operation parameter combinations was 21.5%. The optimal working parameter combination of the strip applicator was the compaction inclination angle of 120 °, the forward velocity of 5 km/h, fertilization depth of 150 mm, and the obtained coefficient of variation of fertilization amount was 15.2%, and the fertilization process was stable and reliable. The research results could provide equipment support for protecting arable land and applying solid organic fertilizer crushing in the black soil area of Northeast China.