西甜瓜有机肥深施机变量排肥装置设计与试验OA

To solve the problems of incapable variable-rate fertilizer discharge,uneven fertilization and easy fertilizer clogging in organic fertilizer deep applicators for watermelon and melon cultivation,a variable-rate fertilizer discharge device for organic fertilizer deep applicators used in watermelon and melon planting was designed.The device mainly comprises components including an organic fertilizer hopper,a double-helix fertilizer conveying mechanism and a fertilizer crusher,etc.Its working principle was elaborated,and parameters were determined via design and calculation of key components.The discrete element method simulation software EDEM was adopted to simulate the fertilizer crushing and conveying performances.The results indicated that the proportion of particles with a size≤30 mm after crushing was increased to 94.34%,and the average conveying capacity of the double-helix auger reached 9.29 kg/s,which satisfied the design requirements.Experimental analysis clarified that the rotational speed of fertilizer discharge exerted the most significant influence on the coefficient of variation of fertilization uniformity and the fertilizer crushing rate.The optimal factor combination was obtained as follows:fertilizer discharge rotational speed of 9.6 r/min,operating speed of 1.9 km/h,and fertilizer crushing rotational speed of 104.7 r/min,corresponding to a coefficient of variation of 27.6% and a crushing rate of 94.8%.Experimental verification proved that the optimized results were reliable,and the performance indicators of the device met the fertilization requirements for watermelons and melons.