Material Movement Analysis And Structure Optimization In High-level Unloading Unit Of Combine Harvester

In order to study the movement state of the material in the high-level unloading device,solve the problem of internal material blockage of the high-level unloading device under the large feeding amount of the combine harvester,this article uses the EDEM software to make Numerical simulation of internal material movement of high-level grain unloading device under different flow rates of 8kg/s,8.5kg/s,9kg/s and 10kg/s.After processing and analyzing the numerical simulation results,the specific high-level unloading grain device optimization and improvement scheme is proposed.Then,use the EDEM software to make simulation and analysis of internal material movement of improved high-level grain unloading device to verify whether the conveying efficiency is improved and the material flow is smooth.Finally,the high-level unloading grain optimization device is processed,trial-made and assembled,and the high-level unloading grain test proves its consistency with the numerical simulation results.In addition,based on the optimized high-level unloading grain device,a set of unloading grain cylinder one-key retracting system was designed,which solved the problem that the existing high-level unloading grain unloading grain can not be returned by one key and the unloading grain is too long.Problems such as continuous grain unloading.The specific work completed in this paper is as follows:(1)Determine the overall design of the high-level unloading deviceBased on the design idea of smooth delivery of vertical,horizontal and vertical horizontal joints of materials,combined with the research status of high-level unloading grain equipment at home and abroad,the overall level of high-level unloading equipment suitable for China’s crawler-type rice-wheat combine harvester model is determined.The design and parameter determination of the auger,transmission,elbow,outer casing and other components were carried out respectively.The three-dimensional modeling and assembly of the components were carried out by using Solidworks 3D modeling software.(2)Numerical simulation of internal materials of EDEM-based high-level grain unloading deviceThe EDEM discrete element software was used to simulate the internal material movement of the high-level unloading device with different flow rates.By extracting the average quantity of materials in the high-level unloading device under the 9.0kg/s flow rate within 2-5s and 8.0kg/s,8.5 The axial velocity and average flow rate of materials in various areas inside the high-level grain unloading device at different flow rates of kg/s,9.0kg/s and 10.0kg/s to determine the specific blockage inside the high-level unloading device.Happening and Study the internal material movement bottleneck.After processing the numerical simulation results,it is concluded that with the increase of the flow rate,the elbow 2 is the most easily blocked part of the material under all flow rates.Therefore,a specific improvement and optimization scheme is proposed for the elbows: the optimum angle between the horizontal line of the horizontal short auger shaft and the parallel line of the inner side of the spiral blade is 74°,and the horizontal short auger spiral blade is outside.The optimal size of the diameter is 268 mm,which can improve the conveying efficiency of the material at the place,thereby improving the overall conveying efficiency of the high-level unloading device and preventing clogging.(3)Test and test analysis of high-level unloading grain device based on optimization and improvementThe improved high-level unloading grain installation is installed on the combine harvester to carry out the actual harvesting and unloading grain test.After comparing and analyzing the unloading grain test and the numerical simulation results,it can be seen that after the high-level unloading device at different flow rates is optimized after the horizontal short auger size design inside the elbow,the average velocity of the internal material in the flow direction of the elbow two horizontal sections increased by 2%-13% compared with the previous one,and the average flow rate increased by2%-29% compared with the previous one.(4)Construction and design of the automatic storage and release system for unloading grain drumThe structural composition of the unloading and unloading system of the grain unloading cylinder was designed,and the appropriate control scheme was selected.The control principle and process of the one-button retractable and unloading system of the unloading grain cylinder are introduced in detail,and the hardware selection of the unloading and discharging system of the unloading grain cylinder is determined,including determining the specific model and posture of the motor by calculating the parameters such as power and power of the motor.The selection of sensors,displacement sensors and limit switches,and finally designed the electrical wiring frame for the one-button retractable system of the unloading grain cylinder.The design of the system lays a solid foundation for the completion of the one-button retracting operation of the unloading grain cylinder.