Crashworthiness similarity of complex cross sectional energy-absorbing tubes based on step thickness variation

The establishment of small-scale models of energy-absorbing tubes is usually limited by process defects, long manufacturing cycles, and high costs due to the complexity of the cross-sectional geometry. In this paper, the geometric variation similarity model construction method of high-speed train multi-cell energy-absorbing tube is studied based on the step thickness. The influence of thickness on the energy absorption characteristics of thin-walled tubes was analyzed by theoretical derivation. The impact simulation of the experimentally verified finite element model was carried out to study the influence of the cross-section shape and the step thickness on the energy absorption characteristics of the energy absorption tube. We also used an iterative procedure to improve the geometric variation similarity model and analyzed the prediction error. The study results indicate that similarity models of simple cross-sectional tubes can be used to efficiently predict the energy absorption characteristics of complex cross-sectional tubes, thus facilitating early verification and shortening the design cycle.