Vibration Reduction Properties of Complex Structures with Three-Layer Acoustic Black Holes in Small Spaces

As a vital part of the autonomous underwater vehicle (AUV), the transducer array is installed within the head section of the AUV and receives acoustic signals from the marine environment. The array output’s signal-to-noise ratio (SNR) determines performance for underwater detection, navigation, and communication. However, during AUV’s operation, the structural vibration induced by its power system and flow noise will severely deteriorate the SNR. Therefore it is crucial for suppressing the vibration transmission into the pressurized plate, which is a mount installed for the transducer array and enclosed in a small space. It aims at reducing vibration in small spaces. In this study, a complex structure with a three-layer periodic acoustic black hole structure (ABH) is used to increase the vibration reduction of the pressurized plate, which is composed of three ABH structures in the radius direction of the pressurized plate and three ABH structures in the thickness direction. The study shows that the three-layer periodic distribution ABH structure used here has a significant vibration reduction effect on the pressurized plate structure, thereby effectively reducing the self-noise of the vehicle.