# Low Noise Structure Design and Experimental Verification of Ship Based on Flexural Wave Band Gap Characteristics

## TL;DR

This paper introduces a new method to reduce low-frequency noise in ships by designing structures that block specific sound waves.

## Contribution

A novel acoustic optimization method using flexural wave bandgaps for ship noise reduction is proposed and experimentally verified.

## Key findings

- An equivalent periodic spring-mass model accurately predicts bandgap properties.
- Selective stiffness modulation achieves an 8.2 dB noise reduction at 31.4 Hz.
- Bandgap-based design is validated through both simulations and experiments.

## Abstract

To address low-frequency vibration and noise issues in ship grating structures, this study proposes a novel acoustic optimization design method based on modulating flexural wave bandgap characteristics. By establishing an equivalent periodic spring-mass coupled beam model to predict bandgap properties, its effectiveness is validated through numerical simulations and experimental testing. By selectively enhancing longitudinal stiffness while weakening transverse components, the bandgap characteristics are effectively tuned to target frequency bands. This approach achieves an 8.2 dB noise reduction at the 31.4 Hz natural frequency. The results demonstrate that bandgap-based design provides a numerically and experimentally validated solution for low-noise ship structures.