Design And Research Of Field Tobacco Stalk Removal Integrated Machine Crushing Device

In view of the large amount of tobacco straw in the fields of Yunnan’s abundant tobacco production,this paper aims to complete the crushing process of the field tobacco straw cleaning machine to facilitate the recycling and transportation of tobacco straw,reduce the labor intensity of farmers,and at the same time respond to the call by the Ministry of Agriculture and Rural Affairs to promote the integrated utilization of tobacco straw.Combining the mechanical characteristics of Yunnan tobacco straw,we analyze the way of shredding,feeding and discharging,carry out the design of shredding device and complete the cooperation with the front pulling device.The main studies in this article are as follows:(1)Mechanical test analysis of tobacco straw.The shear and compression tests were carried out on the culm through the universal test bench,and the analysis of the shear test results showed that the main and secondary factors affecting the shear force of the culm were the diameter cross-sectional area of the culm,the angle of the tool,and the loading speed,and the radial shear test was compared with the axial shear test,and the radial shear force of the culm was greater than the axial shear force of the culm.The maximum compression force of 3482.7N and the average crushing force of 2540.4N were measured by the compression test on the culm,and the compound curve regression model F =626.851 × 1.052 D of the crushing force and average radius of the culm was derived.(2)Theoretical analysis of crushing device.By analyzing the existing feeding method,crushing method and discharge method,the crushing method of dynamic knife cutting and hammer blade impact compound was determined based on the analysis of biomorphological and physical characteristics of the tobacco culm.In order to cooperate with the plucking device,the straw is conveyed to the crushing chambers by feeding rollers with compression devices.Combined with the structural design of the whole machine,the pneumatic discharge can better allow the crushed culm material to enter the collection box.(3)Design of key components of the crushing device.Combined with the agricultural machinery design manual and literature analysis,to determine the end line speed of the hammer blade and dynamic knife,the knife roller spindle speed is 2100r/min;through theoretical productivity calculation of the rod pulling device,combined with the kinematics and dynamics of the knife roller for theoretical analysis,to determine the cutting length of the dynamic knife of the crushing device is 20 mm and the feeding speed of the feed roller223r/min.According to the crushing target,the design According to the crushing target,the aperture of the crushing screen is 15 mm,and the hole spacing is 22 mm.(4)Crushing knife roller simulation analysis.Through the force analysis of the knife roller,the strength of the crushing knife roller is analyzed by using ANSYS for the static simulation analysis of the dynamic knife and hammer blade.The modal analysis of the overall knife roller shows that the working frequency is much smaller than the resonance frequency of the knife roller,so the normal operation will not bring resonance to the knife roller;the dynamics simulation of the overall knife roller through ADAMS shows that the mass center movement is smooth and the knife roller structure is reasonably designed.(5)Discharge fan optimization and fluid simulation.Through the design and modeling of the discharge fan,the internal air flow is analyzed by FLUENT,and the fan is optimized according to the simulation results.After the optimization of the fan again fluid simulation to optimize the performance before and after the comparison analysis,and then the optimization of the fan of different speed simulation analysis,found that with the increase in speed,airflow speed and pressure are significantly higher,comprehensive consideration of the inlet air speed,discharge air speed to meet the conditions of the straw material transport,air volume to meet the productivity requirements of the crushing device,the machine energy consumption ratio,choose the fan speed is 2100r/min...