Optimization and Parametric Study of the Cap Geometry on Collapse Properties of Energy Absorbers under Quasistatic Loading

Document Type : Original Research Paper


1 Mechanical Engineering Department, Bu-Ali Sina University, Hamedan, Iran.

2 Aeronautical Engineering Department, Shahid Sattari University, Tehran, Iran.


In the present research, the influence of cap geometry on the collapse of thin-walled aluminum-made energy absorbers with various section geometries was investigated. For this purpose, a total of 35 different absorbers were subjected to axial quasi-static loading. In this respect, five different section types and seven different cap configurations were considered for the absorbers and their caps, respectively. The analyses were performed in both experimental and numerical methods. The numerical simulations were conducted using LSDYNA Software and experimental tests were performed to verify the numerical investigations. Good agreement was obtained between the experimental data and numerical results. The results indicated that, in all cases, the application of the cap enhanced the crush force efficiency while lowering maximum force at collapse. In the final stage of the research, optimal absorbers for the cases with open-ended and close-ended caps were proposed using Minitab Software based on the response surface methodology.


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