| Corn has become the main food crop in China,which is of great significance to the safety of food production.In most areas in China,although the corn planting has realized the mechanization of sowing,but corn still USES the old manual on demand,such large mechanized dibbling seeding rate way to ensure the quality of seeding,the result is not ideal,qualified rate and survival rate is low,this kind of technique has a great gap compared with advanced foreign technology.In order to achieve the goal of high quality and high yield of crops in China,we must attach importance to the combination of agricultural machinery and agronomy in the future stage to realize precise sowing.From the point of view of the seeding effect of the advanced corn seeder at the present stage,the advantages of the corn precision seeding machine can not only save labor and seed,but also achieve the strong and homogeneous seedling and increase the crop yield under the condition of ensuring the same plant spacing and sowing depth;The corn precision seeding mechanization is the future development direction of corn seeding technology.In this paper,a kind of pneumatic precision corn seed planter is designed.Three kinds of corn seeds,Xianyu 335,Zhengdan 958 and Hongbo 319,which are commonly used in Jilin region,were selected as experimental seeds.The physical characteristics of three kinds of corn seeds were studied in detail.The equivalent diameters of the three kinds of corn seeds were 7.771 mm,8.212 mm and 8.007 mm,respectively.The 1000-grain weights were 335.16 g,392.66 g and 396.00 g,and the water content was 10.66%,12.52% and 13.24%,respectively.The structure and working principle of pneumatic precision corn seed platter were studied.Through the force analysis of four stages of seed filling,seed clearing,seed carrying and seed platter,the value range of positive gas pressure of the platter was obtained from 0.70 to1.10 k Pa.Then,through EDEM-Fluent co-simulation analysis,the performance data of the seed platter in the process of seed filling and seed platter were obtained.The analysis data showed that the optimal parameters of the seed platter were 31.20 r /min,the air pressure was 1.60 k Pa,and the pore diameter was 2.4mm.According to the high speed seeding advocated at the present stage,the diameter of the seeding plate was designed to be 290 mm and the number of holes was24 with the forward speed of the traction machine set at 7～11 km/h.Finally,CATIA software was used to model the seed platter.Each component of the seed platter was made by the factory,and a multi-factor bench test was conducted on the assembled prototype.Three factors and five levels of tests were carried out for different air outlet diameters,air pressure sizes and the speed of the seed platter.According to the experimental results,the optimal performance parameters of the seed platter in high-speed operation were as follows: The operating speed of the seed platter at 9 km/h corresponds to the speed of the seed platter at31.20 r /min,the diameter of the air outlet is 2.4 mm,and the positive air pressure is 1.60 k Pa.At this time,the qualified index of the pneumatic precision corn seed platter is 92.35%. |
