Experimental Study On Second Cleaning Device Of Corn

Jilin province is located in golden corn belt.The corn planting area is large,accounting for 10%-15% of the national corn planting area of 10%-15%.Due to climate reasons,farmers usually have it natural dry after mechanized harvesting and then threshing.In this paper,the research object is the 5TYZ corn thresher produced by Jilin Longxin Agricultural Machinery Manufacturing Co.Ltd.It can reduce the loss rate by means of second cleaning the corn seeds and impurities sucked out during the threshing operation.By consulting relevant documents and analyzing the principle of cleaning,the cyclone separator is selected as the second cleaning device and the experiment is carried out.Firstly,the content and properties of the extractions produced by 5TYZ corn thresher are measured in this paper.The corn accounts for 75.924% of the extractions,corn cob fragments accounts for 23.294%,corn leaf accounts for 0.7% and the light impurity accounts for 0.41%.The water content of corn which takes up larger proportion is 22.179% and its suspension velocity is 12.2m/s.The water content of corn cob fragments which takes up the second large proportion is 25.672% and its suspension velocity is 4.798m/s.The result of 1000 grain weight of corn is 239.495 g.Secondly,it makes the simulation analysis by the establishment of 3D model of cyclone separator with SolidWorks software and leading the geometric model into ANSYS.It discusses the variation of velocity and pressure in gas flow field and the relationship between the velocity of air inlet,the insertion depth of the exhaust pipe and the length of the cone with the pressure drop.The results show that in the single factor simulation,the inlet velocity,the insertion depth of the exhaust pipe and the length of the cone section are linearly related to the pressure drop in a certain range of conditions.And in the multiple factors simulation,when the inlet air velocity is 10m/s,the exhaust pipe penetration depth is 200 mm,and the cone length is 350 mm,the pressure drop value of the gas phase flow field in the cyclone separator is the smallest.At last,the orthogonal test is carried out on the second cleaning device,taking the cleaning loss rate and the impurity rate as the experimental index and inlet air velocity,exhaust pipe penetration depth and cone length as experimental factors.Through the analysis of the experimental data,the optimal combination of parameters under the single index condition is determined,and the significance of the influence factors to the experimental indexes is analyzed.The comprehensive weighting score method is used to analyze the multi-index experimental data,and the optimal parameter combination of the second cleaning device is finally determined as inlet air velocity 12m/s,exhaust pipe penetration depth 250 mm and cone length 350 mm.In this paper,it determines the relationship between inlet speed,exhaust pipe penetration depth and cone length and clearance loss rate and impurity rate by means of numerical simulation and experimental research of various influencing factors of the cleaning device.Under the premise of the loss rate,the second cleaning device can reduce the impurity rate and make second cleaning of extractions produced by 5TYZ corn thresher,so that the loss rate of corn will be reduced,which is of practical significance for improving the efficiency of threshing machine.