Crushing analysis and multiobjective crashworthiness optimization of bitubular polygonal tubes with internal walls

摘要

In order to reduce casualties and property losses in a collision accident, thin-walled structure has been extensively used as energy absorber in crashworthiness design of train. With the help of energy absorber, collision kinetic energy can be controllably dissipated by the plastic deformation of structures. A new kind of multi-cell thin-walled structure called as bitubular polygonal tubes with internal walls(BPTIW) was constructed. The crashworthiness characteristics of BPTIWs were investigated by LS-DYNA. It can be found that the BPTIW with 12 sides has the most excellent crashworthiness characteristics. Therefore, based on response surface method(RSM) and multiobjective particle optimization(MOPSO) algorithm, the BPTIW with 12 sides was selected to optimize the dimensions of cross-sectional configuration under different constraints of energy absorption(EA) and crushing peak force(CPF). The results show that the optimal designs of BPTIW12 under different constraints present excellent crashworthiness characteristics and can be used in the practical engineering.