Novel approach for design of 3D-multi-cell thin-walled circular tube to improve the energy absorption characteristics under axial impact loading

Multi-cell thin-walled structures have recently gained attentions in aerospace and automotive industries for their excellent energy absorption capacity with lightweight. This paper introduces a novel 3D-multi-cell design to enhance energy absorption capability of multi-cell thin-walled tubes by performing a new arrangement of the internal webs and dividing them into multilayers with different angles of orientation. A comparative study of energy-absorbing performance of single-cell, conventional multi-cell and the proposed three-dimensional multi-cell (3D-multi-cell) of thin-walled circular tubes under axial impact loading is carried out using the non-linear finite element code ANSYS-WORKBENCH/LS-DYNA. The numerical results show that the 3D-multi-cell configuration can achieve a significant improvement in the energy absorption per unit mass (SEA) up to 40%, the crush force efficiency (CFE) up to 42.5%, and the energy absorption effectiveness factor (ψ) up to 30.7% in comparison with those of circular tube. Furthermore, it can significantly improve the SEA up to 20%, the CFE up to 36.8%, and the ψ up to 20% in comparison with those of conventional multi-cell configuration. Furthermore, it is found that the number of layers and angle of orientations have a distinctive effect on the energy absorption capacity and the CFE.