Effects of Warm Eddy on Long-range Sound Propagationin the East Sea

Won-Ki Kim; Chang-bong Cho; Joung-Soo Park; Jooyoung Hahan; Youngnam Na

doi:10.7776/ASK.2015.34.6.455

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2015 Vol.34, Issue 6 Preview Page Next Page

Effects of Warm Eddy on Long-range Sound Propagationin the East Sea 동해에서 난수성 소용돌이의원거리 음파전달에 미치는 영향

30 November 2015. pp. 455-462

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Abstract

It is well known that warm eddy is frequently developed through the year in the East Sea. The warm eddy may affect sound propagation due to changes of sound velocity structures in the sea water. To verify the effects of the warm eddy for long-range sound propagation, transmission loss and performance surface, which were used mean direct signal excess range generated by sound propagation modeling using re-analyzed climatology data on March 23th in 2007 were analysed. From these analyses, we found that characteristics of sound propagation in the sea water are changed by the warm eddy, and boundaries of the warm eddy act as a barrier for long-range sound propagation. Furthermore, these disadvantages of the eddy related to sound propagation were increased when the sea bottom depth is shallow.

Keywords

East Sea

Warm eddy

Long-range sound propagation

Ocean bottom depth

동해에는 주변 수온보다 온도가 높은 난수성 소용돌이가 자주 발생되는 것으로 알려져 있다. 이러한 난수성 소용돌이의 발생은 음속구조의 변화를 야기해 음전달특성을 변화시키게 되며, 특히 원거리 음전달에 큰 영향을 줄 것으로 예상된다. 본 논문에서는 난수성 소용돌이가 확인되는 2007년 3월 23일의 수온자료를 재분석한 자료를 이용하여 난수성 소용돌이가 원거리 음전달에 미치는 영향을 분석하였다. 연구를 위해 포물선 방정식 모델을 이용해 음파 전달손실과 평균 직접 신호초과 거리를 이용한 탐지거리 성능분포분석을 수행하였다. 분석결과 난수성 소용돌이의 존재는 난수성 소용돌이가 존재하지 않을 때와는 매우 다른 음전달 특성을 보여주고 있으며, 특히 난수성 소용돌이의 경계는 음전달의 제한적인 요소가 될 수 있기 때문에 원거리 음전달에 불리할 것으로 판단된다. 이러한 난수성 소용돌이에 의한 원거리 음전달의 제한은 해저 심도가 낮을수록 더 커지는 것을 확인하였다.

키워드

동해

난수성 소용돌이

원거리 음파전달

해저면 심도

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Information

Publisher :The Acoustical Society of Korea
Publisher(Ko) :한국음향학회
Journal Title :The Journal of the Acoustical Society of Korea
Journal Title(Ko) :한국음향학회지
Volume : 34
No :6
Pages :455-462
Received Date : 2015-09-25
Accepted Date : 2015-10-27
DOI :https://doi.org/10.7776/ASK.2015.34.6.455

The Journal of the Acoustical Society of KoreaISSN:1225-4428(Print) 2287-3775(Online)한국음향학회

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