Numerical analysis of the effect of tubes distance on the mechanical behavior and energy absorption of nested thin-walled tubes

In this paper, the effect of tubes distance on the mechanical behavior and energy absorption characteristics of nested thin-walled tubes is investigated using LS-DYNA. Thin-walled cylindrical tubes made of aluminum and steel. Axial impact load is carried out and by increasing the distance between the tubes the absorbed energy is calculated. Finally, the optimum distance to maximize this parameter is determined. Results showed that aluminum tubes in both material models used in the analysis, in an almost identical and the same distance (about 4 to 5 mm) from each other had the highest amount of absorbed energy. Steel pipes in both material models, at different distances showed the highest amount of energy absorption, although the number of folds in different distances was the same. Furthermore, the overall crushing and behavior of the steel tubes were different than those of aluminum tubes.