The Journal of the Acoustical Society of Korea (한국음향학회지)

The Acoustical Society of Korea (한국음향학회)
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A Study on Shallow Water Propagation Model with 2-layered Sediment

2개의 해저층으로 구성된 천해 음파전달에 관한 모델 연구

  • Published : 2001.05.01
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Abstract

In order to consider the sediment layer's effect to total acoustic field, we composed a 3 layered fluid model of 2 sediment layers by adding an additional layer to the Pekeris model and found solutions by using Green's function, boundary conditions and Sommerfeld radiation condition. The modes were divided into discrete modes and virtual modes, and confirmed that the characteristic equation to find discrete modes was same as that of Tolstoy and Clay for normal modes. Also, we confirmed that under similar conditions the 3 layered model showed same results as that of Pekeris model. We believe this 3 layered model can be used to study the sediment's effect on the virtual mode of near field.

2개 층으로 구성된 페커리스 (Pekeris) 모델에 해저퇴적층의 영향을 고려하기 위해 1개의 퇴적층을 증가시킨 2개의 해저층으로 구성된 3층의 유체모델을 가정하고 원통형 좌표계에서 그린 (Green)함수와 경계조건, 좀머펠트 (Sommerfeld) 방사조건 등을 적용하여 해를 구했다. 모드는 불연속 (discrete)모드와 가상 (virtual)모드로 구분하여 구했으며 유도된 불연속모드 산출 관계식은 Tolstoy와 Clay의 정규 (normal)모드 생성방정식과 일치함을 확인하였다. 또한, 환경조건을 페커리스 모델의 조건과 유사하도록 조절하여 시뮬레이션을 수행한 결과, 동일한 결과를 보임을 통해 유도된 수식이 조건에 따라서는 페커리스 모델로 환원됨을 확인하였다. 따라서 본 모델이 근거리 음장내의 가상모드에 대한 퇴적층의 영향 연구에 사용될 수 있다고 판단된다.

Keywords

References

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