葡萄园有机肥链式反转开沟施肥机研制与试验

Design and experimentation of a chain reversal trenching and fertilization device for vineyard organic fertilizer

针对葡萄园有机肥施用深度浅,施肥不均匀等问题,该研究设计了一种链式反转开沟施肥机。该机采用先切后抛的形式,实现开沟施肥回填一体化作业,开沟深度为600 mm,通过理论分析确定了影响切土角的关键参数,构建了正置和侧置式两种施肥模式的仿真模型,并分析了两种模式的排肥规律。通过单因素试验,分析了刮板高度、角度和间距对法向接触力和变异系数的影响,并优选了刮板高度、角度和间距,分别为20 mm,90°和180 mm。田间试验表明,排肥变异系数为8.34%,与仿真结果的误差为2.32个百分点,排肥量为0.8~6 kg/m;两次试验的开沟深度稳定性系数分别为93.57%和92.58%,开沟宽度一致性系数分别为96.16%和95.04%,满足农艺要求。研究结果可为其他果园施肥机设计提供理论参考。

Fertilizer application has been one of the most important facilities to advance agricultural mechanization.Particularly,manual fertilization cannot fully meet the large-scale production in recent years.In this article,a chain reversal trenching and application device was presented for the organic fertilizer in orchards,in order to enhance the trenching depth and uniform fertilization.A reverse-chain trenching mechanism was employed with a fixed trenching blade that moved in the opposite direction of the chain.The soil cutting and simultaneous backfilling were allowed within the trench,as the device progressed.A trenching depth of up to 600mm was achieved in the chain trenching mechanisms.The separate backfilling was reduced to leave no visible trenches on the surface after completion.This design was also a streamlined operation.The mathematical analysis of the trenching blade was conducted to establish a mathematical model using Cartesian coordinate transformations.The relationship equation was derived for the cutting angle.Optimal angle parameters were also provided.According to the trenching depth analysis,the hydraulic adjustment cylinders were selected for the trenching device.A scraper-type fertilizer application mechanism was adopted to develop the discrete element simulation models for both upright and sideways fertilizer application modes.The fertilizer distribution patterns were analyzed under the two modes.While both modes were similarly distributed fertilizer,and the forward-facing mode was more suitable for the operations with the larger fertilizer widths,while the sideward-facing mode was with the smaller fertilizer widths.In the two fertilizer application modes,the sideways application mode had better uniformity,especially at the lower forward speeds.Therefore,the application mode of sideward-facing fertilizer was selected to ensure that all organic fertilizer accurately fell into the trench.A single-factor experiment was carried out to explore the effects of scraper height,angle,and spacing on the normal contact force and coefficient of variation.All three parameters shared a significant impact on the coefficient of variation.In a coefficient of variation of less than 15%,the optimal height,angle,and spacing of the scraper were selected to minimize the normal contact force,resulting in values of 20 mm,90°,and 180 mm,respectively.According to these optimal parameters of the scraper,the simulation was conducted to yield a coefficient of variation of 6.02%and a normal contact force of 9.03 N,both of which were lower than those before optimization.Subsequently,a physical prototype was fabricated and field-tested.An average coefficient of variation of 8.34%was obtained for fertilizer distribution,indicating better uniformity.Furthermore,the maximum and minimum fertilizer application tests showed that the quantities ranged from 0.8 to 6 kg/m,thus meeting the fertilization requirements of different plots.The trenching performance tests show that the average trenching depths of two operations were 616.0 and 624.4 mm,respectively,with stability coefficients of 93.57%and 92.58%,respectively,both exceeding 90%.The average trenching widths were 305.4 and 295.4 mm,respectively,with consistency coefficients of 96.16%and 95.04%,respectively,both exceeding 95%.Therefore,the device exhibited excellent performance in the fertilizer distribution and trenching operations,fully meeting the agronomic requirements.The findings can provide a new tool for the deep application of organic fertilizers in orchards,indicating the promising potential prospects.Innovative design and efficiency can also offer valuable insights into the agricultural fields.