Modeling and analysis of hybrid energy absorption devices for aircraft structures

The design of structures according to impact protection or crashworthiness criteria aims for maximum kinetic energy dissipation through progressive component collapse, with the ultimate goal of minimizing the acceleration peaks suffered by occupants. One of the common trends for reducing accelerations in aircraft structures is that of including collapsible absorbers within the main structural design. This communication focuses on the crushing analysis through numerical simulation of thin-walled hybrid energy absorbers. These absorbers combine a confining metallic tube with a core made from composite materials and high-density structural foam. The components are characterized with different crashworthiness metrics, including the energy absorbed by the device or the peak force during the crushing process. The usage of hybrid elements delivers a significant enhancement compared to the single-component counterparts, improving the structural behavior of the aircraft under impact loading and better protecting the occupants. Results show that, at the component level, the usage of inner reinforcements modifies the collapse mechanism of the specimen and increases the specific energy absorption of the device, mainly rooted in the interaction effect between the core and the confining tube.