Wave Damping Rate Over Multi-layer Permeable Bed of Finite Depth

깊이가 유한한 다중 투수층 위에서의 파의 감쇠율

  • Suh, Kyung-Duck (Department of Civil & Environmental Engineering, Seoul National University) ;
  • Do, Ki-Deok (Department of Civil & Environmental Engineering, Seoul National University)
  • 서경덕 (서울대학교 건설환경공학부) ;
  • 도기덕 (서울대학교 건설환경공학부)
  • Published : 2009.04.30

Abstract

Reid and Kajiura(1957) has studied on the wave damping rate over a permeable bed of infinite depth. In this study, wave damping rate over a permeable bed of finite depth is derived by linear wave theory. It is then extended to derive wave damping rates over a double or triple layer, each of which consist of different material. Applying the wave damping rate to the mild slope equation, the wave transmission coefficient over a permeable bed has been calculated. The model has been certificated by comparing with the result of Flaten and Rygg(1991)'s integral equation method in the case of a single-layer bed.

Reid and Kajiura(1957)은 해저면에 무한한 깊이의 투수층이 존재할 경우에의 파의 감쇠율을 유도하였다. 본 연구에서는 유한한 깊이의 투수층이 존재할 경우에의 파의 감쇠율을 선형파이론을 이용하여 유도하였다. 그리고 이를 확장하여 해저면에 재질이 다른 2 층 또는 3 층의 투수층이 존재할 경우에 파의 감쇠율을 제시하였다. 다음으로 이를 완경사 방정식에 적용하여, 해저면에 투수층이 존재할 경우에의 파의 투과율을 계산하였으며, 1층 투수층이 존재할 경우의 수치계산결과를 Flaten and Rygg(1991)의 적분식 방법과 비교하여 검증하였다.

Keywords

References

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