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

Korean Society of Coastal and Ocean Engineers (한국해안·해양공학회)
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Numerical Simulation of Overtopping of Cnoidal Waves on a Porous Breakwater Using the Boussinesq Equations: Comparison with Solutions of the Navier-Stokes Equations

Boussinesq 식을 사용하여 Cnoid 파의 투수방파제 월파 해석: Navier-Stokes 식 결과와 비교

  • Huynh, Thanh Thu (Department of Civil & Environmental Engineering, Sejong University) ;
  • Lee, Changhoon (Department of Civil & Environmental Engineering, Sejong University) ;
  • Ahn, Suk Jin (Research Institute, GeoSystem Research Corporation)
  • 휜탄트 (세종대학교 건설환경공학과) ;
  • 이창훈 (세종대학교 건설환경공학과) ;
  • 안석진 ((주)지오시스템리서치 부설연구소)
  • Received : 2019.03.03
  • Accepted : 2019.03.29
  • Published : 2019.04.30
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Abstract

We approximately obtain heights of cnoidal waves overtopping on a porous breakwater using both the one-layer Boussinesq equations (Vu et al., 2018) and the two-layer Boussinesq equations (Huynh et al., 2017). For cnoidal waves overtopping on a porous breakwater, we find through numerical experiments that the heights of cnoidal waves overtopping on a low-crested breakwater (obtained by the Navier-Stokes equations) are smaller than the heights of waves passing through a high-crested breakwater (obtained by the one-layer Boussinesq equations) and larger than the heights of waves passing through a submerged breakwater (obtained by the two-layer Boussinesq equations). As the cnoidal wave nonlinearity becomes smaller or the porous breakwater width becomes narrower, the heights of transmitting waves obtained by the one-layer and two-layer Boussinesq equations become closer to the height of overtopping waves obtained by the Navier-Stokes equations.

1개층 Boussinesq 방정식(Vu 등, 2018)과 2개층 Boussinesq 방정식(Huynh 등, 2017)을 사용하여 투수방파제를 지나는 cnoid 파의 월파고를 구하였다. 수치실험을 통해 천단고가 낮은 투수방파제를 지나는 cnoid 파의 월파고(Navier-Stokes 방정식으로 구함)가 천단고가 높은 투수방파제를 지나는 통과파고(1개층 Boussinesq 방정식으로 구함)보다 더 작고, 천단고가 해저에 있는 투수방파제를 지나는 통과파고(2개층 Boussinesq 방정식으로 구함)보다 더 크다는 것을 확인하였다. cnoid 파의 파고가 낮을수록 또는 투수방파제의 폭이 좁을수록 1개층 및 2개층 Boussinesq 방정식으로 구한 통과파고가 Navier-Stokes 방정식으로 구한 월파고에 근접한 것을 확인하였다.

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References

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