Evaluation of Crashworthiness Parameters of Metallic Tubes with Multiple Inner Step Tubes Arrangements

Abstract

Response during energy absorption of a tube system is the key for its application in structures under dynamic loading. An ideal energy absorber should behave with a low peak force, high mean crushing force and with a smooth force displacement curve while under dynamic loading. In this particular study, a bunch of metallic 3-step stepped-tubes with ascending number of stepped-tubes in different configurations are placed inside a metallic thin-walled tube and are numerically investigated for its energy absorption characteristics under dynamic axial loads. Stepped-tubes can absorb energy with progressive failure as per specific need of the design but their geometry parameters influence their performance. One of the initial proposed configurations with five stepped-tubes arrangement is further investigated for changing geometry of stepped-tube and sensitivity of energy absorption characteristics with changed geometry are studied. Deformation modes and different energy absorption parameters such as peak value of crushing force, specific energy absorption, mean crushing force and crush force efficiency are plotted for all of the configurations. Results are compared with published numerical and experimental results for the impact of the proposed configurations on energy absorption capability.