Evaluating frame and plate cellular lattice for sandwich core design and material replacement using a digital twin framework

Additively produced lattice cores create new possibilities for designing lightweight sandwich composites with customized stiffness, strength, and multifunctional capabilities. Nevertheless, scaling lattice structures while maintaining mechanical performance remains challenging because of stress concentrations at nodes, strut buckling, skin-core interactions, and the need to validate new designs and alternative materials amid supply-chain limitations. In this work, we assess the effectiveness of using a homogenized representative volume element model (H-RVE) developed for frame-wall hybrid unit cells in compression for a beam in bending. We also assess a digital twin approach for experimental-virtual data validation to replace materials. We compare its effectiveness with a full solid finite element model (S-FE) and a beam-shell element model (BSE). The results show that the BSE provides the best computational efficiency with high accuracy. The proposed framework provides a practical pathway for scalable design, rapid validation, and supply-chain-resilient material substitution in additively manufactured lattice-core sandwich composites.