NUMERICAL STUDY ON SIGNIFICANCE OF WIND ACTION ON 2-D FREAK WAVES WITH DIFFERENT PARAMETERS

This paper presents a numerical study on how the significance of wind action differs when varying the wave parameters. The quasi arbitrary Lagrangian-Eulerian finite element method (QALE-FEM) is used for this purpose. An improved model for wind-excited pressure and wind-driven current, which is recently developed by the authors of this paper [27], is coupled with the QALE-FEM. Many cases involving freak waves with different focusing time/point and frequency ranges under the action of winds are investigated. The results show that the significance of wind actions on freak waves strongly depends on the focusing time, the focusing point and the frequency range. The knowledge does not only help the proper set up of experiments studying wind effects on freak waves but also contributes to the development of a method for predicting freak waves.

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