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Wheat lodging results in great losses of wheat production about 10%~30% every year. It is very important to study the lodging and to find new way to improve the quality of wheat stalks and its anti-lodging characteristics. The study about the changing of wheat stem mechanical properties with the elastic modulus and stem structure is carried on the basement of theoretical model, experimental improvement, and finite element method. Results show that the stem is more difficult to lodge if the ratio is bigger, which can be calculated through elastic modulus multiplying wall thickness and divided by diameter.

By using SolidWorks2010 software 3d entity modeling for the engine crankshaft of the developed tobacco harvest machine was built, and Ansys system combining working conditions to crankshaft with Ansys finite element method was imported. Then the crankshaft's stress result figure in four conditions was got, the stress concentration area was found, comparing and the analysis the the working conditions of the results, thus the basis theory for the engine of the crankshaft structure optimization design and research was provided.

Using the commercial code ANSTS/LS-DYNA, this study has established a Split Hopkinson Pressure Bar (SHPB) finite element model (FEM) of X70 pipeline steel. Moreover, the stress-strain behavior of X70 pipeline steel has been investigated by a simplified Johnson-Cook model. The stress and strain relationship of X70 pipeline steel under different compact speeds is obtained under the high strain rate of 103S-1. The results obtained by numerical simulation agree well with those by experiments, and the parameters of Johnson-Cook model describe accurately the mechanical behaviors of X70 pipe line steel under high strain rate. This conclusion will serve as an important reference for developing and applying materials.

The realistic representation of an irregular geological body is essential to the construction of a particle simulation model. A three-dimensional (3D) sphere generator for an irregular model (SGIM), which is based on the platform of Microsoft Foundation Classes (MFC) in VC++, is developed to accurately simulate the inherent discontinuities in geological bodies. OpenGL is employed to visualize the modeling in the SGIM. Three key functions, namely, the basic-model-setup function, the excavating function, and the cutting function, are implemented. An open-pit slope is simulated using the proposed model. The results demonstrate that an extremely irregular 3D model of a geological body can be generated using the SGIM and that various types of discontinuities can be inserted to cut the model. The data structure of the model that is generated by the SGIM is versatile and can be easily modified to match various numerical calculation tools. This can be helpful in the application of particle simulation methods to large-scale geoengineering projects.