Design And Experiment Of Slider-hole-wheel Precision Hill Direct Seed Metering Device For Rice

Rice is the main grain crop and plays a vital role in the security of grain production in China.Because the yield and benefit of hybrid rice are higher than that of conventional rice,the planting area of hybrid rice is increasing consistently.Rice dry direct seeding is very popular due to its advantages of cost-saving,labor saving and water saving.Meanwhile,rice varieties suitable for direct seeding are constantly being promoted.Therefore,rice precision seeding equipment with stable seeding,high seed row precision,high performance price ratio and consistent with Chinese planting mode is in urgent need in China.Considering the agronomic requirements of 2-4 hybrid rice grains of the field every hole and the material traits of rice varieties,i.e.Zhongnong 2008,Guofeng No.l and Gangyou898,which are widely cultivated in the middle and lower reaches of the Yangtze river area,a slider-hole-wheel hybrid rice precision seeding device were designed.In order to meet the requirements of the hybrid rice precision seeding,this paper adopts the method of theoretical analysis,discrete element method simulation,bench test and field experiment,and the research of the seed metering device performance of slider-hole-wheel hybrid rice precision seeding device has been carried out.The main content of the study is shown as follows:1)Determination of rice material characteristics.Selecting the dry direct seeding hybrid rice varieties of Zhongnong 2008,Guofeng No.1 and Gangyou898,which are widely cultivated in the middle and lower reaches of the Yangtze river area,and measuring the dimension of their axes,thousand-seed weight,angle of repose and physical and mechanical traits such as sliding friction parameters,to provide a design reference of structural parameters of key components of the seeding metering device and the simulation analysis.2)Design of slider-hole-wheel hybrid rice precision seeding metering device.According to the performance requirements of the hybrid rice precision seeding,the structure design of key parts of seeding devise,such as seeding wheel,guard slider and flange,as well as auxiliary parts,seed clearing wheel,regulating plate and seed box,was carried out to provide a theoretical basis for the processing of seeding device.3)Simulation analysis of performance of seeding metering device by the discrete element method and EDEM software.The model of seeding device and rice grains was set up respectively by Sol id Works and EDEM software and the seeding process of seeding metering device was simulated.In order to obtain optimal structural parameters and working parameters of seeding device,taking the qualified rate,miss-seeding rate of seeding and reseeding rate as test index,and the single factor experiment and the three-factors and three-levels orthogonal combination experiment design methods were used to analyze the influence of structural parameters and working parameters on the seeding performance.According to the results of the range analysis,the optimal combination and their effect orders can be determined.4)Bench test and field test of seeding metering device.According to the optimal combination parameters obtained by simulation,the bench test of seeding device was carried out to verify the reliability of simulation,and the field experiments were carried out on zhongnong 2008,guofeng No.l and gangyou 898.The results showed that the slider-hole-wheel seeding metering device had good adaptability to hybrid rice seeds with three different shapes and sizes,and the planting qualified rate,seeding leakage rate and reseeding rate all met the agronomic requirements of rice planting.