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 Three-Dimensional Wave-Current Interactions Due to Permeable Submerged Breakwaters by Using olaFLOW

olaFLOW를 활용한 투과성잠제에 의한 3차원적 파-흐름의 수치시뮬레이션

  • Lee, Kwang-Ho (Dept. of Energy and Plant Eng., Catholic Kwandong University) ;
  • Bae, Ju-Hyun (Dept. of Civil and Environmental Eng., Graduate School, Korea Maritime and Ocean University) ;
  • An, Sung-Wook (Dept. of Civil and Environmental Eng., Graduate School, Korea Maritime and Ocean University) ;
  • Kim, Do-Sam (Dept. of Civil Eng., Korea Maritime and Ocean Univ.)
  • 이광호 (가톨릭관동대학교 에너지플랜트공학과) ;
  • 배주현 (한국해양대학교 대학원 토목환경공학과) ;
  • 안성욱 (한국해양대학교 대학원 토목환경공학과) ;
  • 김도삼 (한국해양대학교 건설공학과)
  • Received : 2018.06.07
  • Accepted : 2018.08.20
  • Published : 2018.08.31
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Abstract

This study aims at numerically investigating the water-surface characteristics such as wave height distribution depending on the current direction around the three-dimensional permeable submerged breakwaters in wave-current coexisting field which has not been considered in detail so far. In addition, the characteristics of the velocity field including the average flow velocity, longshore current and turbulent kinetic energy, which act as the main external forces of formation of salient, are also examined. For numerical analysis, olaFlow which is open source code of CFD was used and the numerical tests included different types of target waves, both regular waves and irregular waves. Numerical results indicated that wave height variation with wave following or opposing a current behind the submerged breakwater is closely related to turbulent kinetic energy. Furthermore, it was found that weaker longshore currents are formed under wave-current coexisting field compared to the non-current conditions, and transport flow is attenuated. As a result, it was possible to understand the influence of current existence and direction (following and opposing) on the formation of the salient formed behind the submerged breakwaters.

본 연구는 파-흐름의 공존장에 설치된 3차원투과성잠제에 관해 흐름방향에 따라 변화되는 잠제 주변에서 파고분포와 같은 수면변동의 특성 및 설상사주의 주요외력으로 작용하는 평균유속, 연안류 및 난류운동에너지 등을 포함한 유속장의 특성을 수치적으로 검토하였다. 수치해석에는 오픈소스 CFD 코드인 olaFlow를 적용하였으며, 대상파랑은 규칙파와 불규칙파로 하였다. 수치해석결과로부터 흐름방향(순방향과 역방향)에 따른 잠제 제간부 배후에서 파고변화는 난류운동에너지와 밀접한 관계를 가지며, 흐름이 존재하는 경우는 흐름이 없는 경우보다 약한 연안류가 형성됨과 동시에 수송유량이 감소되는 것을 확인할 수 있었다. 이로부터 흐름의 유무 및 방향이 잠제 배후에 형성되는 설상사주의 형성과정에 미치는 영향을 파악할 수 있었다.

Keywords

References

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