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Measurement of Underwater Acoustic Energy Radiated by Single Raindrops
Shu Liu1,2,3, Qi Li1,2,3, Dajing Shang1,2,3
1Acoustic Science and Technology Laboratory, Harbin Engineering University, Harbin 150001, China.
Sensors (Basel, Switzerland)
|April 30, 2021
Summary
This study introduces a new method to predict underwater sound energy from raindrops of any size. This research is crucial for understanding how rainfall noise impacts sonar performance.
Area of Science:
- Acoustics
- Environmental Science
- Fluid Dynamics
Background:
- Rainfall is a significant source of underwater ambient noise.
- This noise can disrupt sonar systems, impacting underwater operations.
- Existing research on raindrop noise primarily focuses on sound pressure and frequency, neglecting sound energy.
Purpose of the Study:
- To develop a predictive model for acoustic energy generated by single raindrops of varying diameters.
- To address the gap in understanding the sound energy component of underwater rainfall noise.
Main Methods:
- Derived a formula for underwater sound energy based on a dipole radiation pattern.
- Conducted experiments in a reverberation tank to measure underwater sound energy.
- Analyzed acoustic energy characteristics and kinetic-to-acoustic energy conversion efficiency.
Main Results:
- Developed a model to predict the average underwater sound energy radiated by single raindrops.
- The model can predict total underwater sound energy during rainfall events using drop size distribution.
Conclusions:
- The proposed method provides a means to estimate underwater sound energy from rainfall.
- This model can improve predictions of ambient noise levels and their effects on sonar.
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