Finite Element Modeling And Analysis Of Cassava Stalk Statics Simulation Based On ANSYS

Cassava is an important crop, is also a kind of economic crops, the tuber is an important raw material for preparation of sugar and alcohol in industry. With the cassava widely planted, people carrying out varieties of research for often abandoned cassava stalk. At present, the use of cassava stalk all based on stalk cut or crushed. So the research related to the mechanical properties of cassava stalk is particularly important.For the research of plant stalk's mechanical properties has many directions, such as lodging resistance of plant stalk, cutting performance of plant stalk, bending stability of plant stalk, In this paper, on the basis of cassava stalk mechanical test, application of computer simulation to simulate and analyze the mechanics of cassava stalk in the failure limit state. During the dissertation, analysed composite structure of cassava stalk, gave the relationship of various types of material between the flexible matrix and the engineering constants, and assumed material types of cassava stalk. The material parameters are important data in the simulation analysis, its determine the accuracy of simulation results direct. In the study, used a universal testing machine for testing main mechanical components (xylem, phloem fiber) on stretching and compression, multiple groups of elastic modulus data of xylem and phloem fibers were measured, the use of statistical methods for analyzing test data determined cassava stalk is transversely isotropic materials. According to the relationship of transversely isotropic of elastic coefficient, at the same time reference elastic datas of various plant stalks, to derived out of the shear modulus and Poisson's ratio of the xylem and phloem fiber. Based on elastic datas of xylema and phloem fiber established the finite element model of cassava stem, which simulated cassava stalk's displacement stress, strain, shear stress in the failure limit state. The main contents and conclusions of the study include the followings:(1) Cassava stalk xylem's axial elastic modulus Ez=250.42MPa, the radial and transverse's elastic modulus Ez=Ey=50.01MPa; the shear modulus Gxy=17.60MPa, Gxz=Gyz=92.75Mpa; the Poisson's ratio ?zx=0.42,?zx=?zY=0.35. Cassava stalk phloem fiber's axial elastic modulus Ez=12.24MPa, the radial and circumferential's elastic modulus EZ=EY=1.78MPa; the shear modulus GXY=0.68MPa, Gxz=GYZ=4.67Mpa; the Poisson's ratio ?YX=0.38, ?ZX=?ZY=0.31.(2) The simulation result of cassava stalk model which lengh is40mm in the axial compression failure limit state include the followings:the maximum displacement of stalk on note is1.546mm, the minimum displacement is0.0872mm; the maximum stress is 9.60MPa, the minimum stress is0.469754Mpa; the maximum strain is0.036732, the minimum strain is0.036447. The shear stress of the XY direction on phloem fiber is in the range of-0.002195Pa--0.000231Pa, the shear stress of the XY direction on xylem is in the range of-0.000231Pa?0.000014Pa, the maximum shear stress of the XY direction is at the junction of the xylem and phloem fiber which value is-0.002195Pa, the minimum shear stress of the XY direction is on the xylem which value is0.00014Pa; shear stress of YZ direction and XZ direction has the symmetry, the shear stress of stalk at direction of YZ and XZ are concentrated on-3.07E-10Pa?4.58E-11Pa, the maximum shear stress of YZ or XZ direction is-2.42E-9, the minimum shear stress of YZ or XZ direction is4.59E-11Pa.(3) The simulation result of cassava stalk model which lengh is40mm in the transverse compression failure limit state include the followings: the maximum displacement of stalk on note is7.629mm, the minimum displacement is0.038mm; the maximum stress is7.64MPa, the minimum stress is0.0023469Mpa; the value of strain mainly concentrated in the vicinity of0.389688. The shear stress of XY?YZ?XZ direction present their different laws when pressure model on the lateral, but they all distribute symmetrically. The maximum shear stress of the XY direction is±1,74649Pa, the minimum shear stress is±0.194054Pa; the maximum shear stress of the YZ direction is±0.4562Pa, the minimum shear stress is±0.005063Pa; The maximum shear stress of the XZ direction is±0.260701Pa, the minimum shear stress is±0.028967Pa.In this paper, I utilized finite element simulation software ANSYS to build finite element model of cassava stalk with composite structure, and show us the complete research methods of plant stalk material from the analysis of mechanical parameters to the simulation, To provide a useful reference for other similar materials researched and analysed.