Multi-objective optimization of foam-filled tubes to enhance the crashworthiness characteristics under impact loading

The study presents an understanding of the tube crushing behaviour modified with multiple geometrical configurations. Along with the foam-filling technique, the modifications in a tube geometry are configured in the form of multiple number and shapes of cut-outs. In order to understand the initial buckling behaviour, modified tube structures are subjected to impact loading using finite element (FE) numerical model of split-Hopkinson pressure bar (SHPB) apparatus. The FE analysis of tube deformation is carried out using ABAQUS/Explicit (R). Later on, aluminium foam is filled in hollow tube structures with cut-outs to enhance its energy absorption capacity. Various crashworthiness parameters such as load-deformation profile, peak crushing load, crush load reduction, energy absorption capacity, and energy efficiency are computed and discussed. Tube deformation behaviour is studied on the basis of force transfer rate through the tubes. Tubes with diamond cut-outs are found to be having least force transfer rate value. Foam-filled tubes with cut-outs have shown excellent performance in terms of energy absorption capacity and energy efficiency. Approximately 80% of energy efficiency is achieved in the foam-filled tubes with cut-outs, which is nearly 36.7% and 42.37% higher than the foam-filled tube and hollow tubes without cut-outs, respectively. Moreover, the positive effect of interaction ratio has been observed between the tube and foam material.