• 제목/요약/키워드: moving overset grids

검색결과 2건 처리시간 0.014초

비정상 RANS 법과 중첩격자계를 이용한 횡파중 선박운동 수치해석 (Numerical Analysis of Ship Motions in Beam Sea Using Unsteady RANS and Overset Grid Methods)

  • 박일룡
    • 대한조선학회논문집
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    • 제45권2호
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    • pp.109-123
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    • 2008
  • The present paper presents the CFD result for a beam wave test case. An ONR tumblehome ship model with bilge keels is used. The beam wave test is for zero forward speed and roll and heave 2DOF with wave slope $a_k=0.156$ and wavelength ${\lambda}=1.12L_{PP}$, with $L_{PP}$ the ship length. The problems is solved numerically with an unsteady Reynolds averaged Navier-Stokes approach. The free surface flow is computed using a single-phase level-set method and the motions in each time step are integrated using a predictor-corrector iteration approach which uses dynamic overset grids moving with relative ship motion. The predicted CFD results for motions and forces are compared with experimental data, showing a reasonable agreement.

A site-specific CFD study of passing ship effects on multiple moored ships

  • Chen, Hamn-Ching;Chen, Chia-Rong;Huang, Erick T.
    • Ocean Systems Engineering
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    • 제9권1호
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    • pp.43-77
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    • 2019
  • A local-analytic-based Navier-Stokes solver has been employed in conjunction with a compound ocean structure motion analysis program for time-domain simulation of passing ship effects induced by multiple post-Panamax class ships in the exact condition of a real waterway. The exact seabed bathymetry was reproduced to the utmost precision attainable using the NOAA geophysical database for Virginia Beach, NOAA nautical charts for Hampton Roads and Norfolk harbor, and echo sounding data for the navigation channel and waterfront facilities. A parametric study consists of 112 simulation cases with various combinations of ship lanes, ship speeds, ship heading (inbound or outbound), channel depths, drift angles, and passing ship coupling (in head-on or overtaking encounters) were carried out for two waterfront facilities at NAVSTA Norfolk and Craney Island Fuel Terminal. The present paper provides detailed parametric study results at both locations to investigate the site-specific passing ship effects on the motion responses of ships moored at nearby piers.