Simulation Analysis Of Structure And Effect Of The Subsoiler Based On DEM

As one of the conservation tillage tools, subsoiler plays an important role in the sustainabledevelopment of agriculture. This article on the base of three angles curved subsoilers thatinclude40°,50°,60°and loam to analyze the structure and subsoiling effect with the discreteelement method. The main contents and conclusions of the research are as follows:(1) The current research on subsoiler by the discrete element method mainly stay on thesand, compared with the loam, the particle of sand is smaller, the structure of sand is simpler.This aticle based on the theory of sand and studied loam, tested the soil parameters of topsoiland plow sole of the field trials, including density, shear strength, friction coefficient, etc.(2) Models building. Boundaries models are established by Pro/e software. About soilmodels, the current study by the discrete element method most use particles with the same shaperandomly distributed to build factory, which caused the big difference from the actual soilparticles, neither considered the impact of soil layer. This article based on the differencebetween topsoil and plow sole, established the soil models by dividing soil into two levels: thetopsoil particles models are created by EDEM software template which using a combination ofspherical particles that approximate the shape of the actual soil particles, and establish fourmodels. the model of plow sole is established by replacing large particles with small particleswith modifying the API function so that more clearly observe the crushing process of the plowsole, and at the same time choose Hertz-Mindlin with bonding model as a contact mechanicsmodel.(3) The Discrete Element analysis of the subsoiler. Currently the research on the subsoilerby discrete element simulation mostly to analyze the overall force of the subsoiler. This papernot only analyzed the overall force of the subsoiler, but also segmented the subsoiler, andanalyzed in different parts of the forces. In addition, this paper also analyzed the broken of plowsole and the contact of topsoil particles and plow sole particles, and then analyzed the effect oftillage. Concluded as follows:①The subsoiling depth have the greatest impact on the resistance,followed by speed, least is radian; Under the same circumstances, the horizontal resistance ofsubsoiler is greater than the vertical resistance.②The shovel tip and curved shovel column ofsubsoiler have the larger resistance than other position.③The curve angle of50°subsoiler hasthe least resistance, best effect of crushing and the property of not overturn the soil.(4) The field trials of subsoilers. Considering there’s a big difference between the soil binand the field trials. This paper tested the resistance and effect of tillage of the curve angle subsoilers inclued40°,50°,60°and50°straight subsoiler by the field experiments and got thefollowing conclusions:①Under the same conditions, the curve angle of50°subsoiler hassmaller resistance than the the same angle straight subsoiler, which proved the curved subsoileris better than the straight subsoiler.②The results of field experiments are consistent with thesimulation results, the horizontal resistance error in the field experiments and simulation arewithin the range of8.05%～16.82%, the vertical resistance error in the field experiments andsimulation are within the range of7.05%～16.4%, compared with the soil bin tests, the errorsare reduced, which proved that the parameters and the model is feasible.③After subsoiling, thebulkiness of soil can be improved, the effect of crushing is obvious.④The further optimizationstrategy to the curve angle of50°subsoiler according to the simulation results and the fieldexperiments results is to optimize the blade tip and the curved shovel columns.