Engineering finite element simulation analysis based on Solidworks modeling technology
The rationality of finite element simulation analysis depends to a large extent on the correctness of the model establishment. At present, most of the finite element simulation analysis adopts similar or simple models, which results in a large difference between the calculation results and the actual situation. Based on the powerful modeling technology of 3D design software such as Solidworks, the mathematical model and data conversion and transmission between the finite element analysis software and the general finite element analysis software are realized, and the establishment of the complex model before the finite element simulation is completed to make up for the complicated construction of the finite element software. The lack of models makes the finite element simulation analysis fast, accurate and effective. Taking a single-hole tunnel under complex terrain conditions as an example, the author uses Solidworks to easily and quickly establish a three-dimensional simulation model of the tunnel. And using the data interface function of general finite element analysis software and CAD/CAM program, after the data conversion, the tunnel model is imported into ANSYS, FLAC3D, MIDAS/GTS, COMSOL Multiphysics and other finite element analysis software to complete the Boolean algebra of the tunnel simulation model. The operation and the division of the tetrahedron unit verify that the Solidworks entity and the parametric modeling technology are practical and applicable to the finite element simulation analysis. 1 Introduction to modeling and analysis software 1.1 3D CAD Modeling Software - Solidworks Solidworks is one of the most widely used Mechanical Design Automation softwares. The idea and process of constructing a 3D model is similar to the designer's thinking process. It is powerful and easy to master, especially with real feature modeling capabilities. It is well received by users and provides input/output format converters for almost all CAD software on the market today, which can be easily exchanged with other 3D CAD software such as Pro/E, UG, MDT. 1.2 Large finite element simulation analysis software Large-scale general finite element programs, which are gradually becoming new technical products with strong functions, user convenience, reliable calculation results and high efficiency, and become powerful analytical tools for engineering calculation. At present, the finite element method plays an important role in many fields such as modern structural mechanics, thermodynamics, fluid mechanics and electromagnetics. At present, it is popular in the Chinese engineering community. The widely used large-scale finite element analysis softwares include ANSYS, ADINA, MSC/Nastran, ABAQUS, COSMOS, ALGOR, MARC, FLACAD, and MIDAS. ANSYS software combines finite element analysis, computer graphics and optimization design to form a relatively complete finite element analysis and processing software. It can perform various analysis such as static analysis, dynamic analysis, thermal analysis, electromagnetic analysis and coupling analysis, and can interface with most CAD software to realize data sharing and exchange. FLAC3D is a three-dimensional fast Lagrangian analysis software for continuous media developed by ItascaConsulting Group Inc. It is widely used in the design and stability of slopes and subgrades, shallow foundation and deep foundation engineering, earth dam and concrete dam design, tunnel surrounding rock stability evaluation and support, mining engineering design, etc. An important research tool. MIDAS/GTS represents the latest technology in the development of current engineering software, providing a new solution in the field of tunnel engineering and special structures. MIDAS/GTS provides intuitive visualization of complex geometric models. In addition, in post-processing, it can automatically output simple and practical calculation books in the form of tables, graphs and charts. 2 The establishment process of Solidworks model 2.1 Solidworks modeling ideas The current commercial finite element program can be divided into three phases (Figure 1), pre-processing, solution and post-processing. The pre-processing is to establish a finite element model, complete the unit mesh division, and the pre-processing parametric modeling uses the parametric modeling function of the CAD software to define the data (design variables) to be participated as model parameters, which is convenient for the future software modification model. . Figure 1 Solidworks modeling program diagram Post-processing is the process of collecting and processing analysis, so that users can easily extract information and understand the calculation results. The calculation results are output in various forms to facilitate understanding of the state of the structure and numerical analysis of the structure. The post-processing results can be used to invert the material parameters of the model and adjust the reasonable simulation degree of the model. In the pre-processing, when the local size of the model is modified to the required size according to the calculation needs, since the model built by Solidworks adopts the intelligent size, the overall model size can change with the local size change, and it is not necessary to worry about the reconstruction of the entire model.
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