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Efficiency of wave absorption by the porous of "Taewoo" of Jeju in regular seaway

파랑 중 제주 "테우" 틈에 의한 파 흡수효과

  • Lee, Chang-Heon (Marine and Environmental Research Institute, Jeju National University) ;
  • Choi, Chan-Moon (Marine and Environmental Research Institute, Jeju National University) ;
  • Ahn, Jang-Young (Department of Marine Industrial and Maritime Police, Jeju National University) ;
  • Cho, Il-Hyoung (Department of Ocean System Engineering, Jeju National University)
  • 이창헌 (제주대학교 해양과환경연구소) ;
  • 최찬문 (제주대학교 해양과환경연구소) ;
  • 안장영 (제주대학교 해양산업경찰학과) ;
  • 조일형 (제주대학교 해양시스템공학과)
  • Received : 2013.03.22
  • Accepted : 2013.05.05
  • Published : 2013.05.31

Abstract

In an effort to find the optimum porous of Taewoo through the mathematical model 2 - dimensional tank water experiment among the approached to a problem related to ocean engineering, this study analyzed the porosity by dividing it into 9 cases. As the wave penetrates through the longitudinal porous of the Taewoo model, it was found that there is a wave energy loss because of the phenomenon of the separation of the porous due to the eddy. Looking into the general tendency based on the wave-height meter (probe) data, it was found that the shorter wavelength and higher frequency area, the more reflection coefficients increased, but in contrast, the longer wavelength and lower frequency area, the transmission coefficients showed the increasing trend and energy dissipation was in a similar way with reflection coefficients. In addition, it was found that the bigger the porosity was, the narrower distribution range of reflection coefficients was, and the more its average value decreased. On the other hand the transmission coefficients in direct opposition to reflection was found to show the wider range and the more gradual increase in the average value as porosity was the bigger around the average value. In contrast, energy dissipation rate was found to increase linearly as porosity increased the more around the porosity of 0.2518 but it decreased gradually around the peak point. Through the above results, it is judged that the porous of optimum in the longitudinal direction of the Taewoo model perforated plate was about 2.6cm because it was found that the porosity which produced the lowest reflection and transmission coefficient and the highest energy dissipation. As a result of comparing this to the case where there was no porosity at all, it showed the function of wave absorbing about 31.60%.

Keywords

References

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