Crashworthiness of Nomex® honeycomb-filled anti-climbing energy absorbing devices

摘要

To investigate the energy-absorption characteristics of thin-walled metals and Nomex (R) honeycomb composite structures, Nomex (R) honeycombs with five different specifications were applied to anti-climbing energy absorbing devices. Based on compression tests on Nomex (R) honeycombs, the equivalent numerical model for honeycombs was verified. A finite element model (FEM) for anti-climbing energy absorbing devices was established in Hypermesh. On this basis, the effects of parameters of different honeycombs on absorbed energy of energy-absorbing structure were analysed through LS-DYNA. The results showed that the energy absorption capacity of the anti-climbing energy absorbing devices mainly depended on honeycomb and thin-walled tubes. A Type-2 model exhibited the highest energy absorption capacity, at about 362 kJ, ACT1-3.2-144 honeycomb and thin-walled tubes absorbed energies of 198 and 149 kJ, respectively, which accounted for more than 95% of the total energy absorbed by the whole structure. The results also revealed that the corresponding average buffer force (484 kN) and the maximum peak buffer force (1226 kN) of the Type-2 model were also much greater than those of the other four structures. The buffer force of the Type-2 model remained within 300 to 1000 kN.