Effect of Cell Geometry on the Energy Absorption of Cellular Honeycombs under In-Plane Compression

This study examines the energy absorption capabilities of cellular honeycombs subjected to in-plane compression. ABAQUS finite element analysis is used and cellular honeycombs with different cell geometries are considered. For various cell angles, comparison of simulation results for full size honeycombs and their single cell analogs suggest that the energy absorption can be accurately determined using the single cell model. Cell wall length study shows that the specific energy absorption (energy absorption per unit mass) is higher for cells with shorter vertical walls. Cell wall thickness study shows that increasing wall thickness increases the specific energy absorption. Vertical wall thickness study shows that the vertical walls be thick enough not to buckle, but no thicker, providing the maximum energy absorption for minimum weight. A detailed analysis of cell deformation for different honeycombs and an insight of the underlying physics behind the differences in energy absorption capabilities observed for the different honeycombs are also presented. Nomenclature b = Cell depth h = Height of the vertical wall l = Length of the inclined wall th = Width of the vertical wall tl = Width of the inclined wall α = Cell wall length ratio; ratio of h to l β = Cell wall thickness to length ratio; ratio of tl to l η = Cell wall thickness ratio; ratio of th to tl σ = Stress θ = Cell angle: the angle between inclined cell wall and horizontal direction I