Concurrent optimization of sandwich structures lattice core and viscoelastic layers for suppressing resonance response

This paper studies the optimization design of sandwich structures with lattice core and viscoelastic layers for suppressing structural resonance response in the frequency domain. A concurrent optimization scheme is proposed to simultaneously optimize the damping material topology in the viscoelastic layers and the size distribution of the lattice core. The damping effect of the viscoelastic layers is simulated as hysteretic damping model, and the full method is used to accurately calculate the dynamic responses. Based on the adjoint method, the corresponding design sensitivities are analytically derived efficiently and the Globally Convergent Method of Moving Asymptotes algorithm is adopted. To ensure a smooth convergence in case of mode switching, the mode tracking technique based on the Modal Assurance Criteria is introduced to track the targeted resonant mode. Numerical examples demonstrate the effect of the concurrent optimization in suppressing structural resonance response.