Finite Element Analysis and Optimization of Egg-box Energy Absorbing Structures

This study investigates the characteristics of egg–box energy absorbing structures and the effect of geometrical alterations on their energy absorption attributes. Geometrical models are simulated using ANSYS® and ANSYS/LS–DYNA® finite element packages, as 3D graphical representations, to identify the optimum design parameters of the structural geometry. A simulation-based multi-objective optimization strategy is employed to find a set of optimal solutions, each representing a trade-off point with respect to the conflicting objectives. The aim is to simultaneously minimize the maximum impact force and maximize the energy absorption capacity of the structure as individual objectives. It is concluded that egg–box geometries with most favorable performance in the initial stage of an impact have large vertical apical angles (70? < ? < 89?), thin walls (t < 1mm), short inter–peak distances and small peak diameters. Maximum deformation lengths occur in egg–box geometries with smaller vertical apical angles (0? < ? < 20?), thin walls (t < 1mm), lengthy inter–peak distances and smaller peak diameters.