A Numerical Model to Study the Effects of Aluminum Foam Filler on the Dynamic Behavior of a Steel Tubular Energy Absorber Using a Multi Node Displacement Evaluation Procedure

Abstract

Tubular energy absorbers are usually found in the structures of cars, trains, and other means of transportation. They can absorb high levels of impact energy by plastic deformation during axial folding. The key advantages of this type of energy absorber are the compact dimensions, simple manufacturing, and good energy absorption efficiency. The dynamic behavior of the tube during collapse has a great influence on the total energy absorbed and, consequently, the force transmitted during folding. The optimization of this process may lead to improved energy absorption efficiency, allowing us to reduce the dimensions and costs of the component or improve the crashworthiness of preexisting structures. Foam materials are used in most applications to improve the impact absorption of structures due to its constant load pattern during crushing. They are used, in most cases, as fillers inside empty absorbers such as tubes. In this paper, a numerical model was developed in order to study the possible interactions of foam and tube walls, providing information onhow this relation can influence the deformation modes of the tube. The obtained results showed a direct influence of the foam interaction with the tube walls under the energy absorption and load transmitting characteristics of the component.