Journal of the Korean Society of Marine Environment & Safety (해양환경안전학회지)

The Korean Society of Marine Environment and safety (해양환경안전학회)
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The Effect of Hydraulic Efficiency on the Design Variables of an Overtopping Wave Energy Converter

월파수류형 파력발전구조물의 상부 사면 설계변수에 따른 수력학적 효율 영향 연구

  • An, Sung-Hwan (Dept. of Ocean System Engineering, Gyeongsang Nat'l Univ) ;
  • Kim, Geun-Gon (Dept. of Ocean System Engineering, Gyeongsang Nat'l Univ) ;
  • Lee, Jong-Hyun (Dept. of Naval Architecture and Ocean Engineering, Gyeongsang Nat'l Univ)
  • 안성환 (경상국립대학교 해양시스템공학과) ;
  • 김근곤 (경상국립대학교 해양시스템공학과) ;
  • 이종현 (경상국립대학교 해양시스템공학과)
  • Received : 2021.12.24
  • Accepted : 2022.02.25
  • Published : 2022.02.28
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Abstract

In a wave power generation system, the overtopping system is known as an overtopping wave energy converter (OWEC). The performance of an OWEC is affected by wave characteristics such as height and period because its power generation system is sensitive to those characteristics; these, as well as wave direction, depend on the sea. As these characteristics vary, it is hard for the OWEC to produce power in a stable manner. Therefore, it is necessary to find an appropriate shape for an OWEC, according to the characteristics of the sea it is in. This research verified the effect of the design of the OWEC ramp on the hydraulic efficiency using the smoothed particle hydrodynamics (SPH) particle method. A total of 10 models were designed and used in simulations performed by selecting the design parameters of the ramp and changing the attack angle based on those parameters. The hydraulic efficiency was calculated based on the rate of discharged water obtained from the analysis result. The effect of each variable on the overtopping performance according to the shape of the ramp was then confirmed. In this study, we present suggestions for determining the direction for an appropriately shaped OWEC ramp, based on a specific sea area.

월파된 파도를 이용한 파력발전시스템을 월파수류형 파력발전기 OWEC(Overtopping Wave Energy Converter)라고 한다. OWEC의 성능은 발전 시스템은 특성상 파도의 파고와 주기의 영향을 받는다. 파도는 해양에 따라 파고, 주기, 파도 방향 등의 특성이 다르고 이러한 파도의 다양한 특성 때문에 OWEC는 안정적인 전력을 생산하기 어렵다. 따라서 각 바다의 특성에 따른 OWEC의 적절한 형상에 관한 연구가 필요하다. 본 연구에서는 SPH(Smoothed Particle Hydrodynamics) 입자법을 사용하여 OWEC의 램프 설계가 hydraulic efficiency에 미치는 영향을 확인했다. 총 10개의 모델을 설계하였으며, 선택된 매개변수에 따라 램프의 설계 파라미터를 선택하고 사면의 형상을 변경하여 시뮬레이션을 수행하였다. 해석 결과로부터 구한 유량을 기초로 hydraulic efficiency를 산출하였다. 계산된 hydraulic efficiency를 바탕으로 각 변수가 사면의 형상에 따른 월파 성능에 미치는 영향을 확인하였다. 본 연구에서는 특정 해역에 따른 OWEC 램프의 적절한 형상에 대한 방향을 제시하였다.

Keywords

Acknowledgement

이 논문은 2021년도 정부(교육과학기술부)의 재원으로 한국연구재단의 지원을 받아 수행된 연구임(지역대학우수과학자지원사업, No. 2021R1I1A3057230).

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