Prediction and application of energy absorption characteristics of thin- walled circular tubes based on dimensional analysis

摘要

In this paper, the energy absorption characteristics of a circular tube are studied using the dimensional analysis method. First, circular tubes composed of different materials, namely, mild steel and aluminium alloy, are used in this study, and the material parameters are obtained from tensile tests. A finite element simulation model of an energy-absorbing circular tube is established and validated through experiments. Second, the Hammersley sampling method was used to design an experiment for the energy-absorbing circular tube under three deformation modes (i.e., concertina mode, mixed mode and diamond mode). Dimensional analysis of the deformation displacement, energy absorption and mean crushing force of the energy-absorbing circular tube under the three deformation modes was carried out. Relationships between the deformation displacement, energy absorption and mean crushing force of the energy-absorbing circular tube and the parameters of the impact mass, impact velocity, etc. are obtained by fitting the results of the dimensional analysis. The fitting accuracy is greater than 0.95. Next, the energy-absorbing circular tube impact experiments were performed, and the experimental results were compared with the fitting results. The error between the predictions and the experimental results is within 10%, so the prediction results are accurate. Finally, the equivalent substitution method between the aluminium alloy and mild steel energy-absorbing circular tube is discussed. The results show that the equivalence of energy absorption is the best equivalent substitution method for the lightweight design of an energy-absorbing circular tube and the length and diameter of the energy-absorbing circular tube should be held constant to obtain the equivalent thickness.