Vibration Reduction Method for Power Cabin of Torpedoes Based on Acoustic Metamaterials

The acoustic stealth performance of torpedoes directly affects the safety of the launching platform, the concealment of the torpedo attack, and the effectiveness of wire-guided guidance. However, the current widely adopted vibration and noise reduction means show unsatisfactory effects in controlling the low and medium frequency vibration of torpedoes. In order to solve this problem, this paper investigated the vibration reduction method based on acoustic metamaterials for the power cabin of torpedoes. Firstly, the vibration response characteristics of the power cabin under axial excitation were analyzed, and a local resonance unit structure of the cantilever beam was designed. The bandgap characteristics and vibration reduction effect of the structure were analyzed. Then, for the supporting structure of the power cabin, a vibration reduction scheme based on acoustic metamaterials was proposed, and the simulation analysis finds that acoustic metamaterials have a significant inhibitory effect on vibration within the corresponding bandgap, and the attenuation of some measurement points can be as high as 11.95 dB. Finally, the validity of the vibration reduction scheme based on acoustic metamaterials is verified through tests, which provides an idea for solving the low and medium frequency vibration problem in the power cabin of the torpedo.