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

Korean Society of Coastal and Ocean Engineers (한국해안·해양공학회)
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Energy Loss Coefficient of Waves Considering Thickness of Perforated Wall

유공벽의 두께를 고려한 파의 에너지손실계수

  • Yoon, Sung-Bum (Department of Civil and Environmental Engineering, Hanyang University) ;
  • Lee, Jong-In (Korea Institute of Construction Technology) ;
  • Nam, Doo-Hyun (Daeyoung Engineering Co. Ltd.) ;
  • Kim, Seon-Hyung (Department of Civil and Environmental Engineering, Hanyang University)
  • 윤성범 (한양대학교 공학대학 토목환경공학과) ;
  • 이종인 (한국건설기술연구원) ;
  • 남두현 (대영엔지니어링) ;
  • 김선형 (한양대학교 공학대학 토목환경공학과)
  • Published : 2006.12.31
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Abstract

In the present study extensisve numerical experiments are conducted using the CFD code, FLUENT, to investigate the energy dissipation due to perforated walls for various wall-thickness and flow conditions. A new empirical formula for energy loss coefficient considering the effect of the thickness of perforated wall is obtained based on the results of computational experiments. It is found that the energy loss coefficient decreases as the wall-thickness increases and the maximum coefficient reduction reaches upto 40% of the value calculated using the conventional formulas for the sharp-crested orifice. To check the validity of the new formula the reflection coefficient of waves due to perforated wall is evaluated and compared with the results of existing theories and hydraulic experiments. The result shows that the new formula is superior to the conventional ones.

본 연구에서는 범용난류유동수치모형인 FLUENT를 이용하여 다양한 유공벽의 두깨와 흐름 조건에 대한 수치실험을 실시하고, 그 결과를 이용하여 유공벽의 두께가 고려된 새로운 에너지 손실계수 산정식을 얻었다. 그 결과 유공벽의 두께가 두꺼워질수록 에너지손실계수 ${\alpha}$가 감소하여 기존의 예연오리피스 감식에 의한 값의 최대 40%정도까지 감소함을 할 수 있었다. 새로운 공식의 타당성을 검토하기 위해 본 연구에서 계시한 공식을 이용하여 파 반사율을 구하고 기존의 공식에 의한 반사율 및 수리실험을 통해 측정된 결과와 비교하였으며, 새로운 공식의 우수성이 확인되었다.

Keywords

References

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