Dfinite Element Simulation Of Up-Cut Breakshovel On Harden Soil With SPH Method

Due to the condition limitation of original soil, labor turnover with poor management to cash crop, or excessive use of fertilizer, the contents of organic matter and moisture of soil is low and harden situation is obvious, which affects the agricultural development of hilly land in Southern China seriously. So, researching and developing operating machine with characteristics of small ground-penetrating torque, large plow depth and stabilized operation is urgent.In order to decrease the working power of tillage implement, the method of combination with up-cut breakshovel and down-cut rotary tillage applied on small agricultural machine is proposed. Focusing on harden soil, finite element method is adopted to analyze the optimization design of up-cut breakshovel tool. The main research contents include:1,Based on the knowledge of tillage soil dynamics and soil tillage machine, the up-cut breakshovel tool is designed. Moreover, the value range of its structure cutting angle and structure intersection angle is discussed.2,Based on the material model MAT147 of LS-DYNA, the constitutive model of soil in hilly land and finite element numerical simulation model of high speed soil-cutting are established. Three-dimensional numerical simulation of up-cut breakshovel process based on SPH method of ANSYS11.0/LS-DYNA is carried out.3,Based on orthogonal test design and numerical simulation technology, choice of cutter tooth shape of up-cut breakshovel tool, optimization of structural parameter of cutter point, three-dimensional numerical analysis of up-cut breakshovel process and relational matching of blade width and plow depth up-cut breakshovel tool are presented.In this paper, optimization design of up-cut breakshovel tool adopting SPH method is researched primarily. The results show that SPH method is effective to calculate the deformation of soil material with large strain and high strain rate. Also, this method can reduce the work power and improve work efficiency of soil plowing under the situation of selecting suitable cutter tooth shape, structure cutting angle and structure intersection angle, and considering the match of forward velocity of small agricultural machine, as well as the rotary speed, blade width and plow depth of up-cut breakshovel tool.SPH method's application in optimization design of up-cut deep tillage breakshovel tool lays a solid foundation for optimization design of down-cut rotary tillage tool.