Design Of Cross-flow Fan For Pneumatic Conveying Of Cotton Picker

As an important strategic material,cotton is not only the main raw material of textiles,but also the most important economic crop in my country,and its output ranks second in the world.The mechanized development of cotton production is the future trend.There are many types of mechanized technologies in the whole process,including but not limited to mechanical farming,irrigation,drainage technology,mechanical fertilization,plant protection,mechanical topping and chemical control,chemical defoliation and ripening,mechanical cotton picking,Some of these technologies have been mechanized in straw processing,residual film recycling,and cotton processing.However,there is still a long way to go before it is fully mechanized.Now it is more dependent on imported machinery or manual participation.Imported machinery has high cost,complex structure,and high maintenance costs,making it difficult to achieve full coverage.The role of mechanization is not enough,so it is necessary to fully improve and upgrade domestic machinery to meet the needs of domestic cotton production mechanization.At present,domestic cotton pickers are in the stage of forward development.Among them,the unified harvesting type is relatively mature,but the domestic unified harvesting is relatively mature.The conveying system of the type cotton picker uses a centrifugal fan,which is easy to block when conveying cotton,resulting in low harvesting efficiency,resulting in a "big horse-drawn cart" situation,and the blocked cotton will knot and damage the cotton,which will cause Economic losses.Therefore,the power source of the conveying system of the cotton picker is studied and analyzed to further promote the development of the cotton picker.Aiming at the blockage of the cotton picker,the problem of the power source is studied,and the theoretical analysis of the replacement of the centrifugal fan with the cross-flow fan is made.The main research contents of this thesis are as follows:(1)According to the problems of easy blockage and low efficiency of the existing cotton picker pneumatic conveying device,a three-dimensional model of the centrifugal fan is established to analyze the reason why the cotton picker is easy to block when the centrifugal fan is used.(2)Considering the pressure loss and flow loss of the fan,study the influence of the blade(blade curvature radius,blade twist angle)structure on the internal flow field and output velocity field of the cross-flow fan,and analyze the distribution of velocity and pressure.(3)Study the influence of the shell structure of the cross-flow fan on its internal flow field,average wind speed and fan flow.Considering the aerodynamic characteristics of cotton and the space of the cotton picker,the optimal shape parameters and related characteristic curves of the cross-flow fan are obtained.(4)Based on the conveying system of the cotton picker,compare the differences in the aerodynamic performance(static pressure,dynamic pressure,total pressure,efficiency,shaft power)of the centrifugal fan and the cross-flow fan with the existing parameters,and compare the use of the cross-flow fan compared to the centrifugal fan.Energy saving of fans.This paper is mainly based on theoretical analysis,through simulation to verify the application of the centrifugal fan in the cotton picker,and proposes a plan to replace it with a cross-flow fan.After simulation,it can be concluded that the application of the cross-flow fan in the cotton picker can reduce the blockage of the conveying system.,and can play a role in energy saving.