Crashworthiness Analysis of a Novel Double‐Filled Hierarchical Hexagonal Tube Subjected to Axial Impact

This article presents a novel double‐filled hierarchical hexagonal (DHH) tube. An Abaqus finite element model is utilized to investigate the crashworthiness of this structure under axial impact. A numerical analysis explores the energy absorption (EA) performance across varying different inner hexagon side lengths, fractal orders, and tube masses. The results indicate that specific EA (SEA) increases with the hierarchical order, with the SEA of the second‐order DHH tubes being 9.22–24.70% higher than that of conventional single‐layered hexagonal tubes and 39.20–43.30% greater than that of conventional single‐filled hierarchical tubes. The DHH structure demonstrates optimal performance with an inner hexagon side lengths of 15 mm, achieving the highest SEA across different parameters. This study provides valuable insights for designing hierarchical multicell double tubes with improved EA efficiency.