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Related Experiment Video

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Simulation, Fabrication and Characterization of THz Metamaterial Absorbers

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Reflected Wave Reduction Based on Time-Delay Separation for the Plane Array of Multilayer Acoustic Absorbers.

Hwijin Park¹, Yeong Bae Won¹, Sehyeong Jeong¹

¹Department of Mechanical Engineering, Kyungpook National University, Daegu 41566, Korea.

Sensors (Basel, Switzerland)

|December 28, 2021

Summary

This study introduces an active control technique using multilayer acoustic absorbers to reduce underwater acoustic signal reflections. The method effectively minimizes reflected sound, enhancing performance for various underwater applications.

Keywords:

acoustic absorber active noise control piezoelectric material smart skin

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Area of Science:

Underwater acoustics
Materials science
Control engineering

Background:

Low-frequency noise and signal reflection pose challenges in underwater acoustic applications.
Multilayer acoustic absorbers offer potential for noise attenuation.

Purpose of the Study:

To present a control technique for reducing acoustic signal reflection using a plane array of multilayer acoustic absorbers.
To investigate the effectiveness of active control for reflected sound reduction.

Main Methods:

A plane array of multilayer acoustic absorbers was designed, incorporating piezoelectric transducers, polyvinylidene fluorides, and acoustic windows.
Time-delay separation was employed to distinguish incident and reflected acoustic signals.
Experimental comparison between passive and active control strategies was conducted.

Main Results:

The proposed time-delay separation technique effectively reduced reflected acoustic signals.
Active control demonstrated superior attenuation rates compared to passive control.
Experiments confirmed the efficacy of the smart skin absorber array.

Conclusions:

The developed control technique significantly reduces underwater acoustic reflections.
The plane array of smart skin absorbers is suitable for diverse underwater acoustic applications.
Active control strategies enhance the performance of acoustic absorbers.