Numerical pathologies in snap-through simulations

Aircraft structures operating in severe environments may experience snap-through, causing the curvature on part or all of the structure to invert inducing fatigue damage. This paper examines the performance of beam and continuum nonlinear finite element formulations in conjunction with several popular implicit time stepping algorithms to assess the accuracy and stability of numerical simulations of snap-through events. Limitations of the structural elements are identified and we provide examples of interaction between spatial and temporal discretizations that affect the robustness of the overall scheme and impose strict limits on the size of the time step. These limitations need to be addressed in future works in order to develop accurate, robust and efficient simulation methods for response prediction of structures encountering extreme environments.

► Investigate the robustness of finite element simulations of snap through events.
► Identify and analyze numerical pathologies in such simulations.
► Identify limitations of structural elements associated with these pathologies.
► Discuss the interactions between spatial and temporal discretizations.
► Recommendations for practical use of existing methods in snap-through analyses.