In this paper, based on the principle of local resonance, several new three‐dimensional labyrinth‐type acoustic metamaterials are proposed, and two optimization methods are used to optimize the structures and screen out two structures with excellent performances, that is, model C and model D. Based on Bloch's theorem and the lattice theory, finite‐element simulations are performed on different structural elements to analyze the bandgap properties of the structures. The frequency response spectra were subsequently obtained by analyzing the transmission characteristics of the finite periodic structures. The results show that both novel metamaterial structures have good bandgap characteristics, with the widest width of the first bandgap reaching 1197.2 Hz in the low‐frequency band 0–2000 Hz, the bandgap coverage reaching 59.9%, and the lowest attenuation peak reaching −256.6, and the structures have excellent vibration and noise reduction capabilities.
Meng et al. (Fri,) studied this question.