Design And Analysis Of A New Type Of Rotary Tillage Knife For Paddy

Soil rotary-tillage technology as an important component of the Mechanized tillage and soil preparation technology,can create a kind of good soil granulation structure and surface state,coordinate some factors such as air and water.And it can also help save water and add nutrients,mulch straw and fertilizer at the same time,protect against insects and disease,provide the conditions for sow,grow and field management.With the sustainable development of ecological agriculture's policy implemented,combining agricultural machinery and agronomic together,lead to the requirement of rotary-tillage become higher and higher.At present,rotary-tillage cultivation exist the following problems in our country: tillage depth no enough,winding grass seriously,consumed too much power and the performance of soil throwing is poor,etc.To solve these problems,in this paper,the key component of rotary tiller——rotary blade is designed.This paper carries out researches under the background of the study on cultivated soil in northeast China.First of all,synthesizes many kinds structure characteristics of rotary blade and research methods in the domestic and overseas,associates with the theories and technologies of rotary-tillage,uses theoretical mechanics,numerical analysis and computer optimization and simulation to design two kinds rotary blades——stubble-bury blade and throwing soil blade.At the same time,this paper studies on soil particles and proposes a simplified mechanical model of sticky soil by soil physics and viscous soil mechanics,draws the soil parameters.And on this basis,do some experimental study about rotary-tillage performance comparison and throwing soil performance comparison in Discrete Element Method(DEM)and its simulation software EDEM,to interpret test results.Finally,intensity checking(static analysis and dynamic modal analysis)need to be carried out for two kinds blades Finite Element Method(FEM)and its simulation software ANSYS,in order to improve the blades structure.This paper is mainly carried out the following works:(1)The theoretical analysis of rotary bladesSynthesizes many kinds structure characteristics of rotary blade and research methods in the domestic and overseas.And Then analyses the theoretical kinematics and dynamics characteristics,curve geometric parameters and working parameters.These theories can provide the foundation for the whole system;(2)The design of two kinds rotary bladesThis study associates with the theories and technologies of rotary-tillage,uses numerical analysis and computer optimization and simulation to design two kinds rotary blades—— stubble-bury blade and throwing soil blade.The stubble-bury blade can increase the tillage depth,improve the quality of field work,prevent the winding grass phenomenon.The throwing soil blade can improve the performance of soil throwing,extend its application field.And on this basis,the paper builds its 3D model by computer graphics software;(3)The study on the soil particles and parametersThis study carries out researches under the background of the study on cultivated soil in northeast China.And then this paper studies on soil particles and proposes a simplified mechanical model of sticky soil by soil physics and viscous soil mechanics,draws the soil physical parameters,provide some datum for the next stage's simulation;(4)The rotary tillage virtual simulation in Discrete Element Method EDEMThis study does some experiments based on those datum about soil physical parameters about rotary-tillage performance comparison and throwing soil performance comparison in Discrete Element Method(DEM)and its simulation software EDEM,to interpret test results.And according to analysis results about the displacement and force of soil particles,derives the stress of blades;(5)The intensity checking of blades in Finite Element Method ANSYSThis study simplifies the force model of blades and the datum from EDEM simulation.And then intensity checking(static analysis and dynamic modal analysis)need to be carried out for two kinds blades Finite Element Method(FEM)and its simulation software ANSYS,in order to improve the blades structure.