Crashworthiness multi-objective optimization of the thin-walled grooved conical tubes filled with polyurethane foam

Abstract

The study of energy absorbers is a main concern in various industries. In the automotive industry analyzing the energy absorbers is considered as a solution to minimize the consequences of traffic collision on occupants and enhance the automobile safety. Nowadays, thin-walled tubes have gained massive popularity as one of the most efficient energy absorption systems. In this research, the optimization of crashworthiness parameters in thin-walled grooved conical tubes was performed through computational experiments. Conical aluminum tube with grooves on the internal and external surfaces was simulated under quasi-static loading, while filled with polyurethane foam. Design of experiments method was applied along with validated finite element analysis for better performing and interpreting the results. The applied response surface methodology indicated that the thickness of the tube, foam density, the depth of the groove and the distance between the grooves are associated with energy absorption, respectively. Also, factors such as the density of the foam, the thickness of the tube, the distance between the grooves, groove depth and angle are related with crush force efficiency in that order. Finally, by analyzing all the design criteria, including absorbed energy of tube, mass of tube, the mean crushing force and the maximum crushing force, the optimal density of polyurethane foam and geometric parameters was obtained through both multi-objective optimization process and Pareto diagram. A comparison of results indicated the significance of grooves depth and thickness of tube as the most influential parameters.