A Flexible Meta-Curtain for Simultaneous Soundproofing and Ventilation

We demonstrate a flexible meta-curtain that can simultaneously block the propagation of sound waves of selected frequencies and let air flow through freely. Such a meta-curtain is assembled by two soft and perforated polyvinyl chloride films with an optimized distance between them. The total thickness of the meta-curtain is 1.16 cm and the holes on it have a diameter of 5 cm. The functionality of soundproofing is bestowed by the resonances formed between the films, which is verified by band structure analysis, numerical simulations, and experimental measurements. We experimentally observed sound transmission loss with a peak of 50 dB near 1700 Hz and an average of 26 dB from 1000 Hz to 1760 Hz, which is consistent with the numerical results. Attributing to the softness of the films and the robustness of the resonance, this meta-curtain retains its functionality even at deformations such as bending. Our work paves a way toward soundproof structures with the advantages of ventilation, flexibility, and light weight.

Automated summary

We have demonstrated a flexible meta-curtain that can block selected frequencies of sound waves while allowing air to freely flow through. This meta-curtain is composed of two soft and perforated polyvinyl chloride films with an optimized distance between them. The soundproofing functionality is achieved through resonances formed between the films, which has been validated through band structure analysis, numerical simulations, and experimental measurements. The meta-curtain retains its functionality even when deformed, making it a promising solution for soundproof structures with ventilation, flexibility, and lightweight advantages.