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

Korean Society of Coastal and Ocean Engineers (한국해안·해양공학회)
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Numerical Study on Extended Boussinesq Equations with Wave Breaking

쇄파구조를 고려한 확장형 Boussinesq 방정식의 수치 실험

  • 윤종태 (경성대학교 건설·환경공학부) ;
  • 이창훈 (한국해양연구소 연안·항만공학연구센터)
  • Published : 1999.09.01
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Abstract

A treatment of wave breaking is included in the extended Boussinesq equations of Nwogu. A spatially distributed source function and sponge layers are used to reduce the reflected waves in the computa¬tional domain. The model uses fourth-order Adams predictor-corrector method to advance in time, and discretizes first-order spatial derivatives to fourth-order accuracy, and thus reducing all truncation errors to a level smaller than the dispersive terms. The generated wave fields are found to be good and the corresponding wave heights are very close to their target values. For the tests of wave breaking, although agreement is considered to be reasonable, wave heights in the inner surf zone are over-predicted. This indicates the breaking parameters in the model should be adjusted.

Nwogu의 확장형 Boussinesq 방정식에 쇄파모형을 추가하였다. 입사조건으로 내부조파기법을 사용하였고 경계에는 스폰지층을 사용하였다. 수치적분은 시간에 대해 4차의 Adams 기법을 사용하였고 공간에 대한 1계 미분은 4차의 차분식을 사용하므로써 모든 차분 오차가 분산항보다 작아지도록 하였다. 면내부조파기법을 이용하여 목적파를 잘 재현할 수 있었고 스폰지층에서 파를 감쇄시키므로써 경계에서 연산영역 내부로의 재반사를 억제할 수 있었다. 천수실험을 통해 수심 변화에 따른 파고와 파장의 변화를 살펴보았고 쇄파전후의 파고 변화는 실험치와 전반적으로 일치하였지만 쇄파후의 파고는 실험치보다 큰 값을 보여주었다.

Keywords

References

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