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

Korean Society of Coastal and Ocean Engineers (한국해안·해양공학회)
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3D Numerical Simulation of Water Surface Variations and Velocity Fields around Permeable Submerged Breakwaters under Irregular Waves

불규칙파 조건 하에서 투과성잠제 주변의 수면변동 및 유속장에 관한 3차원 수치모의

  • 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 : 2018.08.06
  • Published : 2018.08.31
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Abstract

In this study, the performance of irregular wave field generation of olaFlow is first verified by comparing the frequency spectrum of the generated waves by the wave-source using olaFlow and the target wave. Based on the wave performance of irregular waves of olaFlow, the characteristics of the velocity field including the average flow velocity, longshore current and turbulent kinetic energy around the three-dimensional permeable submerged breakwaters, which act as the main external forces of the salient formation, are numerically investigated. The numerical results show that as the gap width between breakwaters decreases, the wave height in the center of the gap increases and as the gap width between breakwaters increases, the longshore currents become stronger. As a result, it is possible to understand the formation of the salient formed behind the submerged breakwaters.

본 연구는 olaFlow을 이용하여 먼저 소스에 의한 불규칙파의 조파에서 목표주파수스펙트럼과 조파된 파랑의 주파수스펙트럼과의 비교 검토로부터 olaFlow의 타당성을 검증하였다. 이로부터 불규칙파랑 하 3차원투과성잠제를 대상으로 잠제 주변에서 형성되는 파고분포와 같은 수면변동의 특성과 설상사주의 주요외력으로 작용하는 평균유속, 연안류 및 난류운동에너지 등을 포함한 유속장의 특성을 수치적으로 검토하였다. 수치해석결과에 따르면 잠제 사이의 개구폭이 감소할수록 개구부 중앙에서는 자승평균평방근파고가 증가하지만 개구부 배후에서는 자승평균 평방근파고가 감소하며, 잠제의 개구폭이 넓을수록 강한 연안류가 형성됨과 동시에 수송유량이 증가되는 것을 확인할 수 있었다. 이로부터 잠제 배후에 형성되는 설상사주의 형성원인을 파악할 수 있었다.

Keywords

References

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  1. Numerical Simulation of Three-Dimensional Wave-Current Interactions Due to Permeable Submerged Breakwaters by Using olaFLOW vol.30, pp.4, 2018, https://doi.org/10.9765/KSCOE.2018.30.4.166