Study On The Interaction Mechanism Between Hanging Cup Planter And Soil Of High-Speed Transplanter For Plug Seedling Based On DEM

Hanging cup transplanter has become the most widely used transplanting machine because of its advantages of hole forming and transplanting at one time.Hanging cup type planter is the main working part of hanging cup transplanter,and its operation performance directly affects the hole forming and film hole forming performance,hole forming resistance and planting quality of transplanter.Therefore,it is of great significance to study the motion characteristics of the cup transplanter and the interaction mechanism between the cup transplanter and the soil for the optimization of the mechanical structure and performance of the cup transplanter and the improvement of the planting quality.Based on the high-speed automatic transplanter designed by the research group,this paper studies the dynamic mechanism between the hanging cup type planter and the soil in the planting process.With the help of discrete element simulation software EDEM and the multi-body system dynamics analysis software Recur Dyn,the movement regulation of the hanging cup under the action of soil,the influence regulation of the structure and motion parameters of the hanging cup on the planting hole,and the dynamic behavior of the soil under the action of the hanging cup are analyzed by coupling simulation.With the help of the finite element simulation software ANSYS,coupled with EDEM software,the finite element performance analysis of the hanging cup under the soil reaction force is simulated;Finally,the performance of the planter is analyzed and the conclusion of the simulation test is verified through the indoor soil trough model bench test and field test.The main research work of this paper is as follows:1.Determination of discrete element simulation parameters for soil particle groups.The physical characteristic parameters of soil are obtained through soil texture test,density test,moisture content test,particle size percentage test,triaxial test and direct shear test;The contact parameters between soil particles are determined by comparing the actual and simulated stacking angles,and the bonding parameters between soil particles are determined by the physical characteristics of soil;Other simulation parameters of soil particles are determined according to references;According to the above parameters,the contact mechanics model of soil particles is established.2.The structure and kinematics simulation analysis of the hanging cup planter.The composition and working principle of the high-speed hanging automatic transplanter and its hanging cup planter are analyzed,and the kinematic characteristics of the hanging cup planter are analyzed theoretically;The EDEM-Recur Dyn coupling simulation model of the hanging cup is established,and the movement regulation of the planter under the action of soil is analyzed based on the model.3.Study on the interaction process between hanging cup planter and soil based on EDEM-Recur Dyn coupling.At different planting frequency,the effective hole forming depth of two different shapes of hanging cups and the hole size after soil reflux are analyzed;At different planting frequency,the soil disturbance state and the stress of the hanging cup with two different shapes are analyzed;At the same planting frequency,the hole forming performance of the two hanging cups is analyzed;At the planting frequency of 96 plants / row / min,the resistance of two kinds of hanging cups under the condition of non backflow soil is simulated and analyzed.4.Performance analysis of the hanging cup based on EDEM-Workbench coupling.Through the coupling simulation of EDEM software and ANSYS software,the dynamic reaction force of soil particles on the hanging cup in two soil states is loaded and simulated,and then the strength and stiffness of the two hanging cups are checked and analyzed at the planting frequency of 96 plants / row / min.5.Experimental study on hole formation performance of hanging cup planter.Indoor soil tank tests are carried out on the test bench of the hanging cup planter to determine the hole forming performance of the hanging cup and the hole forming performance on the membrane when the planting frequency is 60,72,84 and 96 plants/ row / min respectively,and the results are compared with the simulation results.The hole forming performance of the hanging cup and the hole forming performance on the film are measured through the field experiment of the transplanter prototype when the planting frequency is 60 and 72 plants / row / min respectively.