Crashworthiness Analysis of the Gradient Fractal Double Square Tube

In this article, the gradient fractal double square (GFDS) tube is presented, inspired by the hollow structure of rice stems. A numerical analysis evaluating the crashworthiness of this structure under axial impact is conducted. In the comparative results, it is indicated that the GFDS structure exhibits a superior crashworthiness coefficient at equivalent mass and wall thickness when compared to other structural designs. Additionally, in the findings from the parametric study, it is revealed that increased GFDS levels correlate with enhanced energy absorption capabilities, allowing for improved crashworthiness with minimal alterations to the initial peak force. Specifically, under identical wall thickness conditions, an increase in GFDS levels results in a 122.32% enhancement in crushing force efficiency (CFE) for the same mass, while the initial peak crushing force exhibits negligible variation, with a potential decrease of 4.28%. The GFDS's capacity to augment CFE while preserving peak force is particularly noteworthy.