Journal of Korean Society of Coastal and Ocean Engineers (한국해안·해양공학회논문집)

Korean Society of Coastal and Ocean Engineers (한국해안·해양공학회)
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Comparison between Variational Approximation and Eigenfunction Expansion Method for Wave Transformation over a Step Bottom

단일계단 지형에서 변분근사법과 고유함수 전개법에 의한 파랑변형 비교

  • Seo, Seung-Nam (Coastal Engineering & Ocean Energy Research Department, KORDI)
  • 서승남 (한국해양연구원 연안개발.에너지연구부)
  • Published : 2009.04.30
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Abstract

In order to compute linear wave transformation over a single step bottom, both variational approximation and eigenfunction expansion method are used. Both numerical results are in good agreement for reflection and transmission coefficients, surface displacement respectively. However x velocity profiles at the boundary of step are seen to be different to each other even though x velocity matching condition is used.

단일 계단지형 위를 지나는 선형 파랑의 변형을 계산하기 위해 변분근사법과 고유함수 전개법을 사용하였다. 이들 수치해를 비교에서 반사율과 투과율 그리고 해면변위는 거의 일치한다. 그러나 계단 경계에서 유속 정합조건이 부여되었음에도 불구하고 계산된 x방향 유속의 수직구조는 차이를 보인다.

Keywords

References

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