新型承载−吸声一体化结构的水下吸声特性分析

Based on the development trend of underwater vehicles towards deep sea environment and quiet working, this paper proposes a novel load-bearing and sound-absorbing integrated structure with potential applications. By adding cavities and square trusses in the core layer, the structure achieves a low-frequency broadband sound absorption from 0.5 kHz to 5 kHz (average sound absorption coefficient reaches 0.72, producing two perfect sound absorption peaks), and maintains a certain pressure resistance. The sound absorption coefficient of the homogeneous multilayer structure is calculated using the transfer matrix theory and compared with the finite element method (FEM), and a good agreement is obtained. The integrated structure is compared with homogeneous structure, cavity-only structure, and truss-only structure. The analysis includes the displacement cloud diagrams, shear strain, energy dissipation, and mechanical energy flow of each structure to investigate the sound absorption mechanism of the load-bearing and sound-absorbing integrated structure. The influences of the cavity size, modulus of panels and core layers on the sound absorption performance are further analyzed. Finally, the effect of hydrostatic pressure on the sound absorption of the load-bearing and sound-absorbing integrated structure is discussed. The results indicate that the structure is insensitive to the change of hydrostatic pressure and can maintain good sound absorption performance even under high hydrostatic pressure.