Experimental Study On The Physical And Mechanical Characteristics Of Corn Stover

China has abundant resources of crop stover,but the overall utilization rate of the contrast is relatively low,most of the stover resources are discarded waste.At this stage,a pressing matter of the moment is to seek an appropriate method to make full use of stover resources.Further analysis of the nature of crop stover,especially in practice need master the mechanical properties of stover and physicochemical indexes,providing reasonable and reliable basis for the design and reasonable use of stover mechanical equipment.In order to research the physical and mechanical properties of corn stover after harvest,collecting corn stover from the test field,making test samples.By measuring,analysis physical characteristics,such as corn stover height,the diameter of different parts,density and moisture distribution in different parts of the skin and the straw stalk.Useing universal test machine to make compress,shearing,bending and tensile test,study the influence that different moisture content,different sampling location and different loading speed have on the corn stover setion,internodes,skin and straw pith mechanical characteristics.The results are as follows:(1)Study on the physical characteristics of corn stover.Analysis physical characteristics of the mature corn stover after harvest,plant height is in the range of 1.60-2.00m.The diameter of corn straw decreases gradually from bottom to top,bottom diameter is in the range of 21.39?29.77mm,the average value is 24.04mm;in the middle part the diameter is in the range of 15.55?23.77mm,the average value is 19.68mm;top diameter is in the range of 9.38?15.36mm,the average vaule is 12.37mm.The density distribution of corn straw skin and pulp gradually decreases from the bottom to the top,the same parts of the skin's density is higher than the density of pulp.The moisture content of corn straw skin and pulp gradually decreases from the bottom to the top,the same parts of the pulp's moisture content is higher than the water content of skin.(2)Study on compression properties of corn straw.With moisture content,sampling position and loading speed as experiment factors,critical pressure value as test indexes to make three factor and two orthogonal rotation combination test.Making the compression mechanical model,the model analysis shows that the average critical pressure of section is 1423.85N,effect of moisture content and sampling position is significantly,loading speed has a certain influence on the critical pressure;the average critical pressure of internodes is 643.48N,the effect of sampling location on compression characteristics is significantly,moisture content and loading speed on the impact are not significant.The critical pressure of the corn stover section is much larger than the internode value.(3)Study on shear properties of corn straw.With moisture content,sampling position and loading speed as experiment factors,critical shear stress as test indexes to make three factor and two orthogonal rotation combination test.Making the shear mechanical model,the model analysis showes that the average critical shear stress of section is 1741.39N and the influence of moisture content and sampling position on the shear properties is extremely significant;the average critical shear stress of internodes is 1217.32N,the influence of moisture content,sampling location and loading rate on shear stress is significantly;the average critical shear stress of skin is 288.63N,sampling position has significant effect on the shear properties;the average critical shear stress of pulp is 438.19N and the effect of sampling position on the shear properties is significantly.(4)Study on tensile properties of corn straw.With moisture content and the sampling position as experiment factors,critical tension as test indexes to make two factor and two orthogonal rotation combination test.Making the tensile mechanical model,the model analysis shows that the average critical tensile force of corn straw skin is 445.5 1N,and the influence of moisture content the sampling position on the tensile properties is significantly.(5)Study on the bending properties of corn straw.With moisture content and sampling position as experimen factors,the critical bending force as the test indexes to make two factor and two orthogonal rotation combination test.Establishing the bending mechanics model,the model analysis shows that the average critical bending force of section is 649.68N,and the influence of moisture content the sampling position on the bending properties is significantly;the average critical bending force of internode is 433.19N,effects of moisture content and sampling position on the bending properties is significantly.The critical bending force of corn starw section is much larger than the value of the internode.