Thin-walled structures optimization as crash energy absorber using DOE and RSM

The optimization of circular aluminum tube as crash energy absorber that usually is used in automobile and train structures is studied in this paper. To simulate a complicated behavior of this kind of crash problem, an explicit finite element software LS DYNA is used. In order to validate the finite element modeling, some FE results have been compared with experimental test results. The Response Surface Method (RSM) which does not require sensitivity analysis of the crushing behavior is applied to maximize the energy absorption and specific energy absorption with the mean crash force as constraint. The D-Optimal design of experiments has been used to reduce the number of needed points for approximation in the Response Surface Method. Design of experiments has been done by the Design Expert software that provides highly efficient design of experiments and optimization. The optimization process has been repeated until the convergence criteria are satisfied.