Crashworthiness analysis of bio-inspired hierarchical multi-cell circular tubes under axial crushing

Abstract

Drawing inspiration from nature’s hierarchical organization, we propose a novel bio-inspired hierarchical multi-cellular circular tubes (BHMC) with a fractal structure. Using an experimentally validated LS-DYNA finite element model, we investigated the impact resistance of this structure under axial loading. Numerical analysis was conducted to explore the energy absorption performance of BHMC tubes with varying numbers of branches, fractal orders, and tube masses. The numerical findings indicate that specific energy absorption (SEA) increases with higher numbers of fractal orders. Specifically, the SEA of 2nd order BHMC tubes surpasses that of conventional multicellular circular and single-layer tubes by approximately 35.07% and 17.10%, respectively. Optimal performance is achieved with the proposed structure featuring tree branching (N = 6) and 2nd order fractal characteristics, yielding the highest specific absorption energy across different parameters. These results offer valuable insights for designing multicellular bilayer tubes with superior energy absorption efficiency, providing an effective guideline for structural optimization.

Keywords:

• Crashworthiness
• hierarchical
• energy absorption
• thin wall structure

Disclosure statement

No potential conflict of interest was reported by the authors.

Data and code availability

The datasets generated during and/or analyzed during the current study are available from the corresponding author on reasonable request.

Additional information

Funding

This work is supported by the National Natural Science Foundation of China (No. 52365036 and No. 52065059).