Journal of Korean Society of Coastal and Ocean Engineers (한국해안해양공학회지)

Korean Society of Coastal and Ocean Engineers (한국해안·해양공학회)
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Reassessment of the Mild Slope Equations

완경사 파랑식들의 재평가

  • 서승남 (한국해양연구원 연안개발연구본부)
  • Published : 2007.12.31
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Abstract

In the derivation of mild slope equation, a Galerkin method is used to rigorously form the Sturm-Liouville problem of depth dependent functions. By use of the canonical transformation to the dependent variable of the equation a reduced Helmholtz equation is obtained which exclusively consists of terms proportional to wave number, bottom slope and bottom curvature. Through numerical studies the behavior of terms is shown to play an important role in wave transformations over variable depth and it is proved that their relative magnitudes limit applicability of the mild slope equation(MSE) against the modified mild slope equation(MMSE).

완경사 파랑식의 유도에 Galerkin방법을 사용하여 수심 의존함수에 대한 Sturm-Liouville 미분식을 엄밀하게 구성하였다. 구한 방정식의 종속변수에 대한 전형적인 변수변환으로 수심, 해저경사 그리고 해저곡률에 대한 항들로 구성된 변형 Helmholtz식을 얻었다. 수치실험을 통해 이 항들이 지형에 의한 파랑변형에 주요한 역할을 보이고 이들의 상대적인 크기에 의해 수정 완경사 파랑식(MMSE)에 비해 완경사 파랑식(MSE)의 적용성이 제한됨을 입증하였다.

Keywords

References

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