Establishment Of Wheat Plant Model And Test Of Material Movement Of Single Longitudinal Axial Flow Wheat Combine Harvester

Aiming at the blockage problem in the material conveying system of the wheat combine harvester,this paper established a discrete element flexible model of the wheat plant,and studied the continuous conveying process of the wheat in the feeding auger-crossing bridgethreshing drum screw feed head.A feed quantity detection device is designed,and a piezoresistive flexible film sensor is used for bench test,and a feed quantity detection model is constructed.The DEM-MBD coupling simulation technology,high-speed photography technology,bench test and sensor detection technology are used for experimental.research,and the law of movement,attitude adjustment,conveying time,axis The change of speed and local material mass flow rate.This article provides technical reference for solving the problem of material conveying blockage of combine harvester.The main research contents are as follows:(1)The main wheat variety Huai mai 40 in the harvest period in Henan Province was selected as the research object.The basic physical parameters such as the geometric size of the wheat plant were measured by the experimental measurement method,and the mechanical properties of the wheat stalk and ears were measured by the ZQ-890B material testing machine.Parameters,using high-speed photography technology to determine the stalk-steel and stalk-stalk collision recovery coefficient,static friction coefficient and rolling friction coefficient,provide theoretical basis and data reference for the establishment of the discrete element flexible model of wheat plants.(2)The EDEM multi-scale particle aggregation method was used to establish the whole-plant discrete element flexibility model of wheat at harvest.Through material characteristics test and EDEM simulation,the whole-plant discrete element flexibility model of wheat was compared with the actual wheat individual plant quality,stalk radial accumulation angle and Wheat ears pile up horns.The results show that the intrinsic parameters and contact parameters of the entire wheat plant discrete element flexibility model are basically consistent with actual wheat,which proves that the established wheat plant discrete element flexibility model can be used for DEM-MBD coupling simulation.(3)The DEM-MBD coupling simulation method is used to analyze the continuous conveying process of the wheat from the feeding auger-crossing bridge-threshing drum spiral feeding head,and the movement law and attitude adjustment mechanism of the wheat in the continuous conveying are obtained.The results show that the spiral blades of the feeding auger,the telescopic fingers and the spiral blades of the threshing drum feeding head are the key components to change the conveying attitude of the wheat;the single factor experiment and the quadratic regression orthogonal rotation combination are designed using the EDEM-RecurDyn coupling simulation method The experiment analyzed the changes in the conveying time,axial speed and local material mass flow rate of the wheat in continuous conveying,and revealed that the feed volume,threshing drum speed,bridge spindle speed and feed auger speed influence the wheat conveying performance The main factor,the threshing drum screw feed head is the key part to solve the blockage.The bench test was carried out with Zoomlion 4LZ-8BZ1 single longitudinal axial flow wheat combine harvester as the research object.The results showed that:when the feed volume is 7.52kg/s,the threshing drum speed is 1083r/min,and the feed auger speed When it is 308r/min and the speed of the bridge spindle is 369r/min,the shortest conveying time is 6.37s.The high-speed photography technology was used to photograph the material conveying situation,and the simulation test was verified.The result showed that the error between the test and the simulation was 4.08%,which verified the reliability of the numerical simulation results.(4)In order to realize the feed quantity detection of the material conveying system of the combine harvester,a feed quantity detection device is designed.The wheat conveying quality is used as the test factor,the collected voltage signal is used as the test index,and the film sensor is used to detect the feed quantity.Experiment,and use bicubic interpolation and noise reduction filtering method to process the voltage signal.The result is:the linear fitting curve of wheat conveying quality and voltage signal:U=-0.22m+5.89,correlation coefficient R2=0.97.Feeding quantity detection model:U=-0.73q+5.89.