Acoustic Band Gaps and Sound Attenuation of Triply Periodic Minimal Surface-Based Metamaterials

This study investigates the manipulation of phonons using triple periodic minimal surface (TPMS) lattices, focusing mainly on noise attenuation for aeronautical applications. Computationally, we obtain the phononic band diagrams for three TPMS lattices of sheet morphologies. Numerical investigations leveraging the bandgap characteristics of these TPMS lattices were used to explore their efficacy in noise attenuation. FRD, Primitive, and Neovius lattices showed a complete bandgap. The Neovius lattice showed the highest band gap width at low frequency and high porosity. In addition to different lattice structures, we investigated the impact of cell size on the bandgap. With an increase in cell size, the frequencies of the bandgap formation decreased. The existence of a complete bandgap within the human audible frequency makes these lattices highly suitable for noise reduction.