Crashworthiness design of multi-cell tapered tubes using response surface methodology

Abstract

In this article, crashworthiness performance and crushing behavior of tapered structures with four internal reinforcing plates under axial and oblique dynamic loadings is investigated. These structures have a tapered form with five cross-sections of square, hexagonal, octagonal, decagon and circular shapes. In the first step, finite element simulations performed in LS-DYNA are validated by comparing with experimental data. The code generated in LS-DYNA is then used to investigate the energy absorption behavior of the tapered structures. Response surface methodology and historical data design technique are employed to optimize the cross section perimeter (or tapered angle) of the tapered structures by considering two conflicting crashworthiness criteria including energy absorptionand peak crushing force. The optimization results show that the optimal tapered angle is enhanced by increasing the number of cross-section sides (or the number of corners). Then, the optimized tapered structures with different cross-sections are compared with each other using a ranking method called TOPSIS to introduce the most efficient energy absorber. The decagonal structure is finally found to be the best energy absorber.