Vibration response analysis of an aircraft structure in terms of crashworthiness by using differential transformation method

Due to importance of certification procedure and safety of occupants, crashworthiness is one of the most principal elements to be considered in the design and production of civil and military aircrafts. In the component level, the crashworthiness of an aircraft structure is significantly affected by many factors including the cross-section of the aircraft structure, boundary conditions of the aircraft structure, and applied crush loading to the aircraft structure. The aim of this study is to contribute to the literature on improving the design of aircraft structures in order to increase the energy absorption properties of the aircraft structures and therefore support the crashworthiness capability of the structures by performing vibration analysis. In this context, after deriving the governing equations of an aircraft structure exposed to an axial crush loading, three different applications are conducted to investigate the effects of the axial crush loading on the dynamic characteristics of the aircraft structure. The findings of the study concluded that vibration characteristics of an aircraft structure subjected to an axial crush loading are affected by the boundary conditions of the structure, material of the structure, cross-section of the structure, magnitude of the axial load applied to the structure, and direction of the axial load applied to the structure. In addition, the findings showed that the response of the structure under ultimate axial crush loading varies depending on the geometriy of the structure, material of the structure and the direction of the ultimate axial crush loading applied to the structure.