On the crashworthiness performance of novel hierarchical multi-cell tubes under axial loading

Abstract

In recent years, the concept of hierarchy has been introduced into crashworthy design to explore an ultralight energy-absorbing structure with outstanding mechanical properties. In this study, a group of novel hierarchical multi-cell tubes (NHMTs) are proposed by replacing every sides of traditional multi-cell tubes with smaller square cells. The finite element model of NHMTs is first established and validated by experimental test. Then, the crashworthiness performance of NHMTs is analyzed and compared with taditional multi-cell tubes (TMTs). The results indicate that NHMTs exhibit superior crashworthiness behavior than TMTs and the hierarchical level has significant effect on the crashworthiness of NHMTs. Furthermore, in order to analyze energy absorption mechanism of NHMTs, the theoretical models of specific energy absorption (SEA) and mean crushing force (MCF) are established and validated. The result shows that the theoretical model of SEA and MCF can accurately predict the energy absorption behavior of NHMTs. This investigation offers a novel technique to design multi-cell tubes with excellent energy absorption capacity.