Design And Experiment Of Air-assisted Sprayer For ’Y’-Shaped Trellis Trees Of Orchard

With the introduction and development of trellis planting technology,more and more orchards began to use this technology in recent years.After continuous trials and improvements,standardized trellis planting has obvious advantages,making fruit tree planting more standardized,orchard management more convenient,harvesting more convenient,and improve the yield and quality of fruits.However,the new cultivation technology lacks the corresponding orchard management machinery.Due to the vastly different tree shapes,the traditional spraying machinery has unsatisfactory effects on the fruit trees on the trellis.According to actual surveys,traditional sprayers are used in trellis orchards,and the following situations often occurred:small sprayers cannot cover the entire canopy,and large sprayers can spray indiscriminately under the canopy,which is redundant and wastes a lot of pesticides.Pesticides deposited in the soil are absorbed by crops and concentrated in plant organs,which then affects the product quality,and the amount of drift is relatively large,which adversely affects the health of the workers.In response to the above problems,this article takes the’Y’-shaped trellis pear trees as the object,with the goal of miniaturization of machinery,improvement of agricultural utilization,and reduction of excessive use of pesticides,a wind-driven sprayer is designed,and the test data is used for analysis and optimization.To explore the influence of different parameters on the pesticide application effect of scaffolding pear trees.The research content of this article is as follows:（1）Take the trellis pear trees as an example,analyze its planting characteristics and specific parameters,and then determine the sprayer index designed for the trellis pear trees,and formulate the spray type.（2）According to the design index of the sprayer,design and select its key components,and configure the whole machine.First,select the type of fan according to the wind demand,determine its model through the fan performance curve,design the sprayer air guide device according to the size of the scaffold,and establish a three-dimensional model.Establish a mathematical model of the air guide device,analyze its internal flow field to assist in selecting its optimal size,and determine the medicine pump model,nozzle model and medicine box,etc.Design and layout the transmission system,finally complete the whole design and processing of machine.（3）Perform performance tests on machines.Three-year-old and six-year-old trellis pear trees were used as the work objects to carry out orchard experiments.The different parameters of the machine were combined,and their influence on the spraying effect was preliminarily explored.The advantages and disadvantages of the sprayer were tested through experiments.The sprayer was improved,a smaller fan was replaced according to the actual wind demand,and the air guide device was changed.The middle part was replaced with a hose,which can be adjusted according to parameters such as tree shape and tree age.Optimize the transmission system to realize stepless speed regulation,which is convenient for adjusting the wind speed and air volume.The structure of the whole machine is more compact,which improves the problem of too small ground clearance of the sprayer.The improved equipment was tested,and the effects of operating speed,air outlet wind speed,and air outlet height on the coverage rate of target droplets,the amount of droplets deposited per unit area of the target,and the amount of droplets deposited per unit area of the ground were studied.Design-Expert software was used to establish a response surface to analyze the test data,and optimize the operating parameters of the machine.The results show that the air sprayer has an operating speed of 0.8m/s,outlet wind speed of 22m/s,and the height difference between the middle of the air outlet and the middle of the pear tree canopy at 5.1cm,the target droplet coverage rate is 39.79%,the droplet deposition per unit area of the target is 9.89μL·cm^-2,and the droplet deposition per unit area is 5.41μL·cm^-2,which meets the requirements of the air-driven orchard sprayer operating standards.