PROPOSAL OF NUMERICAL WAVE FLUME FOR WAVE OVERTOPPING COMPUTATION CONSIDERING WIND EXTERNAL FORCE

Masami Kiku, Koji Kawasaki

Abstract


Strong wind blows around seawalls when wave overtopping disasters occur. Consequently, wind effects on wave overtopping are essential in designing seawalls. However, the relationship between wind and wave overtopping rate has not been clarified quantitatively because it is difficult to estimate the wind effects by hydraulic model experiments. The objective of this study was to introduce wind external force to a two-dimensional numerical model based on a numerical wave flume ‘CADMAS-SURF’. A TimerDoor method, which was a computational method for the motion of water particles and air bubbles, was improved to represent wind-induced acceleration motion. The proposed method was validated through comparison with hydraulic model experiments. As a result, the dimensionless wave overtopping rates obtained by the numerical computations were in reasonable agreement with the experimental results. It was found that the proposed model is useful for wave overtopping simulation considering wind effects.

Keywords


wave overtopping; wind external force; CADMAS-SURF; numerical simulation; wave deformation; irregular wave

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References


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DOI: https://doi.org/10.9753/icce.v34.waves.8