基于离散元法的分层施肥靴参数优化与试验

Parameter optimization and test of layered fertilization boot based on discrete element method

为实现一次性满足作物不同生长时期对肥料的需求,提高肥料的利用率,设计一种分层施肥靴。通过理论计算确定其主要结构参数,利用离散元法对肥料分层过程进行仿真试验,并结合响应面分析法得出分层施肥靴结构参数及运行条件的最佳组合;设计台架试验检验上下两层肥料的分肥比例,进行田间试验对仿真分析结果进行验证。结果表明:圆杆数量对肥料分层效果影响极显著(P<0.01),行进速度对肥料分层效果影响显著(P<0.05),圆杆直径对肥料分层效果影响不显著(P>0.05)。确定最优组合参数为:圆杆数量6根,圆杆直径4mm,行进速度6.04km/h,此条件下上下两层肥料距离的变异系数为4.57%;在不同施肥量条件下,上下两层肥量比为4∶6,变异系数的仿真值与试验值相对误差不超过4%,证明利用离散元法对分层施肥装置进行参数优化具有可行性。该研究为精准对行分层施肥机的改进提供了参考,对推动新疆精量减肥具有一定的意义。

In order to meet the demand of fertilizer in different growing periods and improve the utilization rate of fertilizer,a kind of layered fertilization boot was designed.According to the material characteristics of fertilizer particles,soil particles and the design requirements of layered fertilizer particles in soil,the key parameters of each part of the layered fertilization boot were calculated theoretically.SolidWorks software was then used to generate layered fertilization boot with different structures,which were imported into EDEM software for simulation test.The test results showed that the number of round bar had an extremely significant effect on the layered effect(P<0.01),the traveling speed had a significant effect on the layered effect(P<0.05),and the diameter of round bar had no significant effect on the layered effect(P>0.05);As the standard to measure the effect of fertilizer layering,the variation coefficient of the distance between the upper and lower layers of fertilizers was 4.57%;Under different fertilization application conditions,the ratio of the upper and lower layers was 4∶6;The upper layer fertilizer particles were located between10-15 cm beneath the surface and the lower layer fertilizer particles were located between>15-20 cm beneath the surface.The upper and lower layer fertilizer spacing was about 5 cm and the relative error between the simulation value and the test value of variation coefficient is less than 4%,which proved that the discrete element method was feasible to optimize the parameters of the layered fertilization device.This study provided references for the improvement of the precise layered fertilization machine,and had certain significance for promoting Xinjiang’s precise weight loss.