Design And Experiment Of Potato Fertilizer Discharge Device Based On Mixed Application Of Organic Fertilizer And Chemical Fertilizer

In order to solve the problems of poor overall fertilization uniformity and inconsistent mixing ratios of various fertilizers in the existing potato planting and fertilization device,this paper designs a potato fertilizer discharge device that combines an external groove wheel mixing device and a double spiral conveyor device based on the required organic fertilizer mixing ratio for potato fertilization and the working principle of the existing fertilizer discharge device,The optimal working parameter combination of various components of the fertilizer discharge device was obtained through EDEM simulation experiments and bench tests.The main research content and conclusions are as follows:(1)Measure the physical and mechanical parameters of fertilizer particles and fertilizer box materials,using urea,diammonium phosphate,potassium sulfate,and potato specific organic fertilizer required for potato fertilization as the experimental objects.Conduct experiments at a ratio for potato fertilization,and measure their moisture content,triaxial size,density,and friction coefficient,providing data support for the structural design of the fertilizer discharge device and subsequent simulation experiments.(2)Conduct structural design and theoretical analysis on the fertilizer discharge device.On the basis of the existing structure and working principle of the fertilizer discharger,for the external groove wheel mixing device,based on the existing agronomic requirements for fertilizer box and potato fertilization,the size of the fertilizer box and the size of the external groove wheel are designed and optimized,and the fertilizer discharge amount of the groove wheel is theoretically analyzed;For the double helix conveying device,the size of the double helix and its shell was optimized and designed.Through theoretical analysis of its theoretical fertilizer discharge and uniformity,the parameter range of key components that affect its theoretical fertilizer discharge and uniformity was determined,providing data support for simulation and bench tests.(3)Using the discrete element simulation software EDEM,simulation experiments were conducted on the external groove wheel mixing device and the double screw conveying device,and key component parameters were optimized.In the simulation experiment of the external grooved wheel mixing device,four fertilizers were poured into the corresponding fertilizer boxes according to the required proportion for potato fertilization.By adjusting the rotational speed of the four external grooved wheels,all four fertilizers were discharged at the same time.Through theoretical analysis and simulation experiment verification,the rotational speed of the four external grooved wheels were obtained as follows: the rotational speed of the urea external grooved wheel was 40r/min,and the rotational speed of the diammonium phosphate external grooved wheel was 20r/min,The speed of the potassium sulfate outer groove wheel is set at80r/min,and the speed of the potato specialized organic fertilizer outer groove wheel is set at100r/min;In the simulation experiment of the double helix conveying device,the double helix pitch,center distance,and rotational speed were used as experimental factors,and the fertilization error and coefficient of variation of fertilization were used as experimental indicators.Response surface experiments were conducted with reference to national standards and relevant agricultural norms to analyze the impact of various parameters on fertilizer discharge performance and optimize the parameters.The optimal working parameter combination was obtained: the double helix pitch was 48.7mm,the center distance was 61 mm,and the fertilizer discharge shaft speed was 85.2r/min.(4)Conduct validation tests on the optimal structural parameters of the fertilizer discharge device using the discrete element simulation software EDEM.Simulation experiments were conducted on the fertilizer discharge device to verify its optimal working parameter combination.The experimental results under the optimal parameter combination were as follows: the error of the total fertilizer application amount was 5.5%,and the coefficient of variation of the fertilizer application amount was 5.65%,all of which were small,indicating that the fertilizer discharge device was complete and the overall fertilization uniformity was good.Calculate the coefficient of variation of fertilizer application for each fertilizer in the total grid: the coefficient of variation of fertilizer application for urea is 5.32%,the coefficient of variation of fertilizer application for diammonium phosphate is 5.50%,the coefficient of variation of fertilizer application for potassium sulfate is 5.58%,and the coefficient of variation of fertilizer application for organic fertilizer is 4.18%.It can be seen that the coefficient of variation is relatively small.Measure the mixing ratio of four fertilizers in each grid,The results indicate that the distribution of the four fertilizers in each grid is relatively uniform and the mixing ratio is consistent,providing a theoretical basis for subsequent bench tests.(5)Conduct bench validation tests.The potato fertilizer discharge device test bench was constructed using the optimal structural parameter combination from the previous simulation experiment.Repeated experiments showed that the average error of the total fertilizer application amount in the bench test was 6.55%,and the average coefficient of variation of the fertilizer application amount was 5.68%,all of which were small.This indicates that the fertilizer discharge device is complete and the overall uniformity of fertilizer discharge is good.Calculate the coefficient of variation of fertilizer application for the four fertilizers in the total grid: the average coefficient of variation of fertilizer application for urea is 5.36%,the average coefficient of variation of fertilizer application for diammonium phosphate is 5.55%,the average coefficient of variation of fertilizer application for potassium sulfate is 5.65%,and the average coefficient of variation of fertilizer application for organic fertilizer is 4.25%.It can be seen that the coefficient of variation is relatively small.Measure the mixing ratio of the four fertilizers in each grid,The results show that the distribution of the four fertilizers in each grid is relatively uniform and the mixing ratio is consistent,and the simulation test of the optimal parameters of the fertilizer discharge device is in good agreement.Therefore,the fertilizer discharge device can achieve uniform mixing of organic and chemical fertilizers,and the mixing ratio is consistent.