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

Korean Society of Coastal and Ocean Engineers (한국해안·해양공학회)
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Galerkin Finite Element Model Based on Extended Mild-Slope Equation

확장형 완경사방정식에 기초한 Galerkin 유한요소 모형

  • 정원무 (한국해양연구소 연안.항만공학연구센터) ;
  • 이길성 (서울대학교 지구환경시스템공학부) ;
  • 박우선 (한국해양연구소 연안.항만공학연구센터) ;
  • 채장원 (한국해양연구소 연안.항만공학연구센터)
  • Published : 1998.12.01
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Abstract

A Galerkin's finite element model incorporating infinite elements for modeling of radiation condition at infinity has been developed, which is based on an extended mild-slope equation. To illustrate the validity and applicability of the present model, the example analyses were carried out for a resonance problem in the rectangular harbor of Ippen and Goda (1963) and for wave transformations over circular shoals of Sharp (1968) and Chandrasekera and Cheung (1997). Comparisons with the results obtained by hydraulic experiments and hybrid element method showed that the present model gives very good results in spite of the rapidly varying topography. Numerical experiments were also performed for wave transformations over a circular concave well which may be an alternative to conventional wave barriers.

본 연구에서는 지배방정식으로 확장형 완경사방정식을 사용하고 무한요소를 이용하여 방사조건을 처리하는 Galerkin 유한요소 모형을 수립하였다. 수립된 모형의 타당성과 적용성을 입증하기 위하여 Ippen and Goda((1963)의 완전개방 직사각형 모형항만에서의 항만 공진과 Sharp(1968) 및 Chandrasekera and Cheung(1997)의 원형 천뢰상을 전파하는 파랑 변형에 대한 수치해석을 실시하였다. 수리모형실험 및 복합요소 모형에 의한 결과와의 비교를 통하여 본 모형이 급경사 지형에도 매우 양호한 결과를 제시함을 확인하였다. 마지막으로 방파제의 대안으로 고려될 수 있는 원형 해저 우물을 설정하고 이를 지나는 파의 변형 특성을 검토하였다.

Keywords

References

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