Research On Mechanical Properties And Threshing Damage Mechanism Of Grain

The injury of grain is linked to internal and external stress,is also concerned with mechanical properties.In this paper,the physical and mechanical properties of grain are researched.The relationship between internal organization and mechanical properties of grain is analyzed.This article introduces different types of gain damage during threshing.And the conceptions of the outer damage index,the inner damage index, the standard damage index etc.are defined in order to make quantitative evaluation.The mechanical properties of grain are analyzed by the software of ANSYS.The location of maximum tensile stress is on the area of farinaceous endosperm and embryo when the top of grain is loaded.And the location of maximum tensile stress is on the area of embryo.It finally shows that the fracture of the seed is resulted by the tensile stress.Utilizing the impact test device of agriculture material invented by ourselves,the grains of different varieties,different moisture content,and different height are researched while the grains are impacted.At last,the failure energies of grains are obtained.Spike-tooth threshing unit is used as an example,the relative velocity between the grain and spike-tooth is calculated during the collision process between the grain and threshing component while the stress crack just occurs in the grain.Finally,it proves that the experimental results are according with the results of theory analysis.