Journal of the Institute of Convergence Signal Processing (융합신호처리학회논문지)

The Korea Institute of Convergence Signal Processing (한국융합신호처리학회)
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Study on Plunging Wave Breaking near Ship Bow

선수 주위의 플런징 쇄파 연구

  • Koo, Bon-Guk (Department of Naval Architecture and Marine Engineering, Changwon National University)
  • 구본국 (창원대학교 조선해양공학과)
  • Received : 2021.09.09
  • Accepted : 2021.09.29
  • Published : 2021.09.30
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Abstract

Flow features near the ship bow such as wave breaking, small scale phenomena have been studied using numerical methods. In this study, the bow shaped wedge was adopted which is from previous paper [1, 2] and the conditions of simulation were Re = 1.64 × 105) and Fr = 2.93. Star CCM+, one of the commercial CFD programs has been used for the simulations. Simulation results such as wave profiles near the ship bow, shape of plunging jet, air entrainment, and wave breaking process have been compared with previous experimental and numerical studies. Overall results showed good agreements with previous studies. Profiles of bow waves showed that overturning jet has been created and broken along the wedge. Plunging wave breaking has been observed along the wedge and four components of plunging wave breaking process were shown. It is confirmed that velocity near the overturing jet significantly increased during plunging wave breaking.

선수 주변의 쇄파 과정 및 작은 스케일의 특징과 같은 유동 특성을 조사하기 위해 수치적 연구가 수행되었다. 본 연구에 사용된 쐐기형 선수의 형상은 이전 연구 [1, 2]에서 가져온 것이며 계산 조건은 Re = 1.64 × 105 및 Fr = 2.93이다. 상업용 전산유체역학(CFD) 소프트웨어 중 하나인 Star CCM +을 사용하여 수치 시뮬레이션을 수행하였다. 전반적인 선수 주변의 파 프로파일, 플런징 제트 모양, 공기 혼입 및 쇄파 과정과 같은 결과는 다른 실험 및 수치 연구와 비교되었고 일치하고 있는 것을 확인할 수 있었다. 선수파 프로파일은 쐐기 앞에서부터 뒤로 가면서 뒤집힘 제트가 형성되고 마지막으로 제트가 쇄파 되는 것을 볼 수 있다. 플런징 쇄파 현상도 쐐기 모양을 따라가면서 일어나는 것을 알 수 있고 이전 플런징 쇄파에서 나타나는 플런징 쇄파의 4가지 과정을 보여 주고 있다. 플런징 쇄파 시 제트 주위의 속도가 급격하게 커지는 것을 확인할 수 있다.

Keywords

Acknowledgement

이 논문은 2021~2022년도 창원대학교 자율연구과제 연구비 지원으로 수행된 연구결과임.

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