Underwater Wide Low Frequency Pressure Sound Insulation Structure Design

The influence of noise in practical engineering applications and life cannot be ignored.Sound insulation has also become an important research direction.At the same time,in underwater acoustic engineering,sound insulation performance under low frequency conditions is also an important indicator of acoustic stealth of underwater vehicles.Underwater sound insulation is also an important research content:In this paper,the acoustic-solid coupling vibration model of stiffened plate structure is established,and the theory is compared with COMSOL simulation results.The principle of underwater acoustic sound insulation of stiffened plate structure is discussed,and the parameters of sound insulation performance of stiffened plate structure are analyzed and optimized.Aiming at the demand of underwater wide and low frequency sound insulation,this paper introduces quasi-zero stiffness structure into traditional reinforced structure,and uses its high static stiffness and low dynamic stiffness to realize wide and low frequency sound insulation under high hydrostatic pressure.Firstly,the mechanical characteristics of quasi-zero stiffness structure are analyzed.The quasi-zero stiffness structure based on positive and negative spring type is selected.According to the required pressure resistance requirements,the relevant parameters of the quasi-zero stiffness structure are optimized to reach the quasi-zero stiffness state under this pressure.The high stiffness reinforcement in the traditional stiffened plate is replaced.Considering the fluid-solid coupling boundary conditions,the theoretical model of the quasi-zero stiffness sound insulation structure is established.Finally,the sound insulation performance of the structure under hydrostatic pressure is calculated,and combined with COMSOL simulation,the underwater sound insulation performance of the designed structure is explored.The results show that the low frequency sound insulation of the quasi-zero stiffness stiffened plate structure designed under hydrostatic pressure is significantly higher than that of the known stiffened plate structure.The quasi-zero stiffness stiffened plate is designed in series to design a three-plate structure that can achieve quasi-zero stiffness under different water pressures.Considering the fluid-solid coupling boundary conditions,the theoretical model of underwater sound insulation of quasi-zero stiffness three-plate structure is established.According to the required pressure bearing requirements,the structural parameters are optimized and the underwater acoustic wide-low frequency sound insulation structure that can bear multiple pressures is obtained.