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

Korean Society of Coastal and Ocean Engineers (한국해안·해양공학회)
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Experimental Study for Wave Overtopping Volume Estimation of Rubble-Mound Structure Using Pressure-Current Speed Relationship

압력-유속 관계를 이용한 경사식구조물의 월파량 추정 실험

  • Jong-In Lee (Department of Civil Engineering, Chonnam National University)
  • 이종인 (전남대학교 공과대학 토목공학과)
  • Received : 2024.10.10
  • Accepted : 2024.10.22
  • Published : 2024.10.31
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Abstract

In this study, a new method for wave overtopping measurement was proposed. The proposed method utilize the pressure-current speed relationship and the wave overtopping height. The relationship between pressure and current speed was studied using a flow channel, and the validity of the method for measuring wave overtopping was examined using a two-dimensional wave flume. After installing a pressure gauge in the current channel, the change in pressure according to the increase in current speed was measured, and the relationship between pressure and current speed was derived. The proposed method showed high accuracy when the incident angle was normal condition, and it was confirmed that the accuracy decreased somewhat as the incident angle increased. The reason that the accuracy is somewhat lower under oblique incidence conditions is because the sensitivity to pressure and current speed is high. In addition, when the amount of wave overtopping was large, the relative error increased, but the correlation coefficient between the measured and the estimated overtopping volume was relatively high. It was confirmed that the proposed method was possible as a method for wave overtopping measurement in the field.

본 연구에서는 압력-유속 관계와 월파고를 이용하는 월파량 계측방법을 제안하였다. 압력-유속 관계는 흐름 수로를 이용하였고, 제안된 계측방법의 적정성은 2차원 조파수로를 활용하여 검토하였다. 흐름수로내에 압력계를 설치한 후 유속의 증가에 따른 압력의 변화를 계측하여 압력-유속 관계식을 도출하였다. 제안된 계측방법은 파랑이 구조물에 직각으로 입사할 때 정도 높게 나타났으며, 경사입사 조건에서 정확도가 다소 낮아지는 것을 확인하였다. 경사입사 조건에서 정확도가 상대적으로 낮아지는 것은 압력과 유속의 민감도가 높기 때문으로 판단된다. 또한 월파량이 증가할 때 상대적인 오차도 다소 증가하는 경향을 보였지만 계측된 월파량과 추정된 월파량의 상관관계는 비교적 높게 나타났다. 본 연구에서 제안한 방법은 실해역에서 월파량 계측에 적용이 가능할 것으로 판단된다.

Keywords

Acknowledgement

본 논문은 2024년도 해양수산부 재원으로 해양수산과학기술진흥원의 연구비 지원(과제번호: 20220180)을 받아 수행된 성과이며, 연구비 지원에 감사드립니다.

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