Recently, bionic thin-walled structures have attracted widespread attention in automotive safety design because of their excellent crashworthiness behavior and weight efficiency. In this paper, inspired by the evolution laws and microstructure of plant stems, a group of bionic tubes with $m$ parts and $n$ layers (PmLnBTs) are proposed and investigated by theoretical prediction and numerical analysis. Theoretical models of PmLnBTs are developed to predict the specific energy absorption. Finite element model is conducted with LS-DYNA and validated by a quasi-static axial crushing experiment. The accuracy of the theoretical model is verified by numerical analysis, and the maximum relative error is less than 7%. Furthermore, parametric studies are conducted to investigate the effects of geometric parameters on the energy absorption capability of PmLnBTs. The results indicate that the PmLnBTs exhibit superior crashworthiness performance compared to traditional bi-tubular circle tubes. Moreover, when designing such a bionic energy absorber, it can effectively improve the crashworthiness performance by appropriately increasing the number of layers, reducing the outermost circle diameter or avoiding innermost circle diameter value too large or too small. The findings of this paper provide a guidance for the design of energy absorber with excellent energy absorption performance.

近年来，仿生薄壁结构因其出色的耐撞性和重量效率而受到汽车安全设计的广泛关注。在本文中，受植物茎的进化规律和微观结构的启发，一组仿生管$米$ 零件和 $ñ$提出并通过理论预测和数值分析研究了PmLnBTs层。建立了PmLnBT的理论模型来预测比能量吸收。有限元模型是使用LS-DYNA进行的，并通过准静态轴向破碎实验进行了验证。通过数值分析验证了理论模型的准确性，最大相对误差小于7％。此外，进行参数研究以研究几何参数对PmLnBTs能量吸收能力的影响。结果表明，与传统的双管圆管相比，PmLnBTs具有更好的耐撞性能。此外，在设计这种仿生能量吸收器时，可以通过适当增加层数来有效提高耐撞性。减小最外圆直径或避免最内圆直径值太大或太小。本文的发现为具有良好能量吸收性能的能量吸收器的设计提供了指导。