Research On Experiment And Simulation Analysis Of Soybean Collision With Soil

In this paper, selecting soybean seeds and soil in Northeastern China as the research objects, tests on the physical and mechanical properties of the soil have been conducted as well as analyzing the collision process of soybean and soil by high-speed imaging technique. Planting experiments were done at laboratory table with simulation analysis of seeding process by Discrete Element Method using software EDEM to compare the simulation and experimental results. Thus we put forward an original method on analyzing displacements of soybean seeds bouncing and rolling after contacting soil by Discrete Element Method. The main contents and results are as follows:(1) Determination of the physical and mechanical parameters of soil particles. Parameters conclude the particle size distribution of the soil, soil moisture content, soil bulk density, friction coefficient, etc. Model of soil particles has been built using microsurgical techniques. The study provide a basis for simulation analysis parameters of discrete elements and selection of models in the seeding process.(2) Analyzing the collision process of soybean and soil by high-speed imaging technique and varying four conditions concluding soil moisture content, dropping height of the soybeans, the contact angle of the bevel and soil particle size, this paper obtained restitution coefficients in four conditions to explore the effect of different factors. Simulation Verification of oblique impact tests are conducted using software EDEM. By comparing the experimental and simulation results, correction of restitution coefficients between soybeans and soil generating from the discrete element simulation analysis has been made.(3)Applying the seeding performance laboratory table as experimental equipment, the bench test has been carried out to analyze the impact of soil moisture, dropping height, conveyor speed and seeding shaft speed on variation characteristics after the soybeans touching soil. A three dimensional discrete element model of metering device and soybean particles has been established. The simulation results were compared with the results of bench tests to verify the feasibility of simulation analysis. It provided an original method on analyzing displacements of soybean seeds bouncing and rolling after contacting soil by Discrete Element Method.