Development Of Variable Ratio Fertilizer And Directional Centrifugal Spreader For Mulberry Field

In order to reduce the burden of silkworm farmers and improve the level of fertilizer used in mulberry field,variable ratio fertilizer and directional centrifugal spreader for mulberry field is designed and manufactured.Physical and mechanical parameters of four kinds of fertilizer particles,namely,nitrogen fertilizer,phosphate fertilizer,potash fertilizer and organic fertilizer,were measured.According to the collision principle,the collision recovery coefficient of fertilizer was measured by high speed camera.The stiffness coefficient of fertilizer was measured by universal testing machine,including density,porosity,rest Angle,three-dimensional size and other parameters.Solid Works was used to conduct three-dimensional modeling of parts,and discrete element software EDEM was used to simulate the movement of fertilizer particles.According to the requirements of fertilizer application,the size and shape of the grooved wheel were designed and calculated.It was concluded that the working length of the grooved wheel was 60 mm,the radius was 30 mm,and the number of conical arc grooved wheel was 12.In order to ensure the change proportionmeter fertilizer mixing uniformity is good,the wheel speed,the groove cone angle and radius of the conical body simulation,simulation of single factor experiment cone tests showed that the cone angle of 50 °,cone radius of 25 mm,groove wheel speed is 15 r/min,the four kinds of fertilizer mixing standard deviation smaller;Study different blade shape on the spreader plate spreader width,and the influence of the uniformity of the spreader,simulation of six different shape blade spreader plate spreader,comprehensive breadth of spreader,fertilizer distribution coefficient of variation and fertilizer distribution,choose simple structure,spreader width narrow,fertilizer distribution coefficient of variation of small curved shape blade spreader plate;On directional spreader mechanism of active plate length,height and fold the corner as factors,Isaac fertilizer distribution variation coefficient as evaluation indicators,the orthogonal experiment simulation,analysis of variance on distribution coefficient of variation of the pecking order for length,fold the corners and height,poor analysis of the optimal combination of length 450 mm,80 mm and 100 ° corner;The simulation and experiment verify that by adjusting the Angle between movable plates,the trajectory of fertilizer can be changed and the directional fertilizer can be realized.In order to ensure the overall stability and safety,finite element analysis was carried out on the frame and chassis of the fertilizer distribution device.The frame of the fertilizer distribution device was203 MPa with a maximum displacement of 11.6 mm,the chassis with a maximum stress of30.6 MPa and a maximum displacement of 0.46 mm,meeting the design requirements.Taking the distribution variation coefficient of fertilizer as the target,the interaction between the centrifugal disk speed,walking speed and the distance between the fertilizer dropping port and the center of the core disk was simulated.Through the establishment of regression model and response surface analysis,it was found that the interaction between walking speed and speed had a significant impact on the distribution variation coefficient.The objective function was optimized under the constraint of various factors under actual working parameters,and the optimization results were as follows: the rotational speed was290.128 r/min,the walking speed was 0.571 m /s,the distance was 88.21 mm,and the minimum coefficient of distribution variation was 7.61%.Processing after the completion of the prototype,the prototype performance determination of straight run partial test and cornering ability,determination of climbing ability,speed and performance measurement,determine the performance parameters of the prototype work,field verification test shows that under the optimal parameters,the distribution coefficient of variation is 9.05%,and the predicted value of relative error is 18.92%,the prototype spreader has good uniformity.