The Journal of the Acoustical Society of Korea (한국음향학회지)

The Acoustical Society of Korea (한국음향학회)
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Acoustic insertion loss by a bubble layer for the application to air bubble curtain and air masker

기포층 음향 삽입손실 연구: 기포커튼과 에어마스커

  • 박철수 (한국해양과학기술원 부설 선박해양플랜트연구소) ;
  • 정소원 (한국해양과학기술원 부설 선박해양플랜트연구소) ;
  • 김건도 (한국해양과학기술원 부설 선박해양플랜트연구소) ;
  • 문일성 (한국해양과학기술원 부설 선박해양플랜트연구소) ;
  • 임근태 (한국해양과학기술원 부설 선박해양플랜트연구소)
  • Received : 2020.04.08
  • Accepted : 2020.05.21
  • Published : 2020.07.31
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Abstract

This paper derives the insertion loss for the bubble layer of an air bubble curtain and an air masker which are used to reduce ocean anthropogenic noise such as the piling noise and the ship noise. The air bubble curtain is considered as a 'fluid-air bubble layer-fluid' model and the environment for the air masker is simplified as an 'vacuum-thin plate-fluid-air bubble layer-fluid' model. The air bubble layer in each model is assumed as the effective medium which has the complex wavenumber and the complex impedance corresponding to the bubble population distribution. The numerical simulations are performed to examine the insertion loss depending on the bubble population, the void fraction, and the thickness of the layer.

해양구조물의 파일링 소음을 줄이기 위한 기포커튼과 선체 진동에 의한 수중방사소음 차단을 위한 에어마스커에 대하여 각각의 삽입손실 해석해를 유도하였다. 해석해를 구하기 위해 기포커튼과 에어마스커를 각각 '유체-기포층-유체' 그리고 '진공-평판-유체-기포층-유체'의 단순 모델로 가정하였고, 각 모델에서 해당 기포층을 복소수 형태의 파수와 임피던스로 규정된 유효매질로 치환하였다. 수치 모의를 통해 기포의 분포, 기포율, 그리고 기포층의 두께에 따른 삽입손실의 특성을 살펴보았다.

Keywords

References

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