Design And Research On The Corn Recycling Device With Vibrating Screen And Fan On Top

The current corn harvesting method in our country is still mainly ear harvesting,and the corn harvester will lose the kernels during the process of peeling the ears.In order to reduce the grain loss and improve the economic efficiency of corn harvesting,this article has launched a research on the grain recovery device of the corn harvester.The main research contents are as follows:1.Designed an upper-mounted fan vibrating screen type grain recovery device.This paper analyzes the source of grain loss during corn harvesting,and proposes a method to use airflow to turn bracts and separate the encased grains,and then use vibrating screens to achieve grain recovery.2.Theoretical analysis of the upper fan vibrating screen type grain recovery device.According to the working principle of the grain recovery device,the selection and design of the fan,the kinematic analysis of the vibrating screen driving mechanism,the dynamic analysis of the material on the screen,and the design of the vibrating screen were carried out.Through theoretical analysis and design,the structural parameters of the grain recovery device for the upper fan vibrating screen are determined.3.The simulation analysis and field test analysis were carried out on the airflow field in the recovery room.Using Fluent to simulate and analyze the air flow field in the recycling room,and compare the air distribution in the recycling room with or without the air distribution plate.It is found that adding the air distribution plate can effectively improve the distribution of the air flow field in the recycling room and increase the grain recovery rate.Field experiments were carried out on the factors that can affect the grain recovery rate in the airflow field.The optimal working parameter combination of the airflow field was obtained through the field experiment as the fan speed 1000r/min,the wind inclination angle 15°,and the grain recovery rate was about 70%.4.The coupling simulation analysis of the grain recovery process of the grain recovery device is carried out.The coupling of Fluent and EDEM was used to simulate and analyze the grain recovery process,and the simulation results were post-processed.By observing the movement posture of the bracts,it is found that the bracts can fully flip before falling into the vibrating screen,so as to achieve the effect of separating the grains wrapped in it.Aiming at the two factors that affect the performance of grain recovery,the number of articles and the size of sieve holes,single-factor simulation experiments were carried out.By observing the trajectory of the bracts and the trajectory of the grains,it was determined that 5 articles should be selected for each article,with an interval of 122.5mm.By observing the trajectory of the grains and counting the number of grains and short stalks through the sieve,it is determined that the sieve holes should be 25mm×25mm long strips.5.With the grain recovery rate as an evaluation index,field experiments were carried out for the factors that affect the performance of grain recovery.Design-Expert is used to conduct single factor analysis,response surface analysis and target value optimization on the experimental data.The optimal working parameter combination is the fan speed 1000r/min,the vibrating screen speed 300r/min,and the operating speed 3.62km/h.Under these conditions,the grain recovery rate is about 85%,which meets the engineering application of the corn combine harvester.