The development of pressure-resistant sound-absorbing materials is crucial for enhancing the stealth performance of underwater vehicles operating at great depths. In this paper, a pressure-resistant metastructure is proposed, and an analytical model for its acoustic impedance is derived. Through structural optimization, the low-frequency sound absorption bandwidth is further extended. The results demonstrate that the proposed metastructure achieves broadband low-frequency sound absorption based on a plate–rubber–cavity coupling resonance mechanism. Experimental validation conducted in a pressurized impedance tube shows that under hydrostatic pressures ranging from 0.5 MPa to 3 MPa, the average sound absorption coefficient between 500 Hz and 10 kHz remains above 0.8. These findings confirm the effectiveness of the proposed configuration in broadening the low-frequency absorption bandwidth while maintaining stable acoustic performance under varying hydrostatic pressures. The study provides a robust platform for the development of underwater artificial functional materials and offers a novel approach for designing noise reduction structures suitable for deep-sea environments.
Zhou et al. (Tue,) studied this question.