FINITE STRAIN PROBLEMS IN ANSYS AND LS-DYNA. APPLIED NUMERICAL METHODS VERIFICATION
Present-day finite element method (FEM) packages, such as ANSYS and LS-DYNA, are multiple objective complexes for the analysis and a solution of the broad audience of tasks in different areas of physics. In all these packages possibilities for problem solving in geometrically nonlinear setting are announced. However the analysis of domestic both foreign references and simples tests have allowed to place, that the numerical methods used now by the most popular packages for solving of finite strain problems, are insufficiently correct and give an adequate estimation only in special cases. The refusal from an offsets and strains smallness hypothesis in solid mechanics reduces in significant problems which till now up to the extremity are solved, despite of the urgency for practical applications.
In this article the main attention is given to inspection of reasonableness of the outcomes obtained at calculations of tasks with finite strains in FEM packages. The verification scheme is offered and trying is made to outline boundaries of applicability of two popular packages (ANSYS and LS-DYNA) for finite strains problems solving.
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