Strength optimization of ultralight corrugated-channel-core sandwich panels

Novel ultralight sandwich panels, which are comprised of corrugated channel cores and are faced with two identical solid sheets, subjected to generalized bending are optimally designed for minimum mass. A combined analytical and numerical (finite element) investigation is carried out. Relevant failure mechanisms such as face yielding, face buckling, core yielding and core buckling are identified, the load for each failure mode derived, and the corresponding failure mechanism maps constructed. The analytically predicted failure loads and failure modes are validated against direct finite element simulations, with good agreement achieved. The optimized corrugated channel core is compared with competing topologies for sandwich construction including corrugations, honeycombs and lattice trusses, and the superiority of the proposed structure is demonstrated. Corrugated- channel-core sandwich panels hold great potential for multifunctional applications, i.e., simultaneous load bearing and active cooling.