Crashworthiness Design for Honeycomb Structures Under Axial Dynamic Loading

Abstract

For a honeycomb structure used for absorbing crash energy and protecting the safety of human or instruments, the bigger the specific energy absorption (SEA) is, the more popular it would be when the peak crushing stress (σp) was retained small enough. In order to improve the energy absorption capacity, crashworthiness optimization for honeycomb structures with various cell specifications are studied in this paper. Detailed numerical models are established for those honeycomb structures by using an explicit finite element method code LS-DYNA. The numerical simulation results are then used as the design samples for constructing metamodels. The optimal Latin hypercube design (OLHD) method is employed for the selection of sampling design points in the design space, and the polynomial functions, radial basis functions (RBF), Kriging, multivariate adaptive regression splines (MARS), and support vector regression (SVR) are utilized to formulate the two optimal objectives SEA and σp. It is found that the polynomial function is the most efficient in constructing the crashworthiness metamodels of honeycombs among the above-mentioned methods. Then, the polynomial function models of SEA and σp are chosen as the surrogate models in the crashworthiness optimization. In order to further validate the polynomial function models, the polynomial function models of SEA and σp are compared with the analytical solutions based on Wierzbicki's theory and Kunimoto and Yamada's theory, respectively. An excellent correlation has been established. As such, the multi-objective particle swarm optimization algorithm (MOPSOA) is applied to obtain the Pareto front of SEA with σp of the honeycomb structures with various cell specifications, which has resulted in a range of optimal designs of honeycomb structures by the multi-objective optimization.

Mean compressive stress constitutive equation and crashworthiness optimization design of three novel honeycombs under axial compression

“…Once the meta-model has been built, it can be used to find the optimum. To obtain optimized response for honeycomb subject to axial compression, RSM is applied which has been demonstrated to be extremely helpful in these cases [23][24][25][26]. Hence, this method is employed to forecast m SEA and peak  of honeycomb subjected to axial compression.…”

“…Li et al [25] found the most optimized alternative square honeycomb structure via employing the RSM in crashworthiness design. The radial basis functions (RBF), Kriging, multivariate adaptive regression splines (MARS), and support vector regression (SVR) were utilized by Yin et al [26] to predict SEA and peak  in optimization of honeycomb structure. They pointed out that different meta-models may provide rather different modeling accuracies and response values.…”

Multiobjective crashworthiness optimization of multi-layer honeycomb energy absorber panels under axial impact

“…In their study, explicit solver of LS-DYNA FE code has been employed to perform the crashworthiness analyses. Yin et al [13] have optimized energy absorbers of honeycomb type with various cell specifications. In their optimizing process, the specific energy, and peak crush stress has been aimed as objective functions while the single wall thickness, double wall width and branch angle of the "Y" column have been set as the optimization variables.…”

Size and shape optimization of aluminum tubes with GFRP honeycomb reinforcements for crashworthy aircraft structures

“…While all of them improve the performance of the structure [22], the honeycomb has proved to be excellent in bettering the response of the complete structure [23,24,25]. Miller et al [26] proved that a modified honeycomb cell resembling an hourglass shape can improve the buckling strength of the inner reinforcement under axial load cases, while Xue and Hutchinson [27] also studied the behavior of square sandwich panels.…”