An Improvement of Wave Refraction-diffraction Effect in Swan

Jaw-Guei Lin

《Journal of Marine Science and Technology》 21卷2期 (2013/04) Pp. 198-208

https://doi.org/10.6119/JMST-012-1207-1

並列摘要

SWAN, a wind wave model, has been modified to take into account wave refraction-diffraction effects from the extended mild-slope equation when wind waves pass through a extremely uneven sea bottom in the presence of current. In our modified model, the diffraction correction parameter introducedby Holthuijsen et al. [10] has been adjusted to better predict the combined effect of the higher-order bottom effect, wave-bottom interaction and wave-current interaction. After a preliminary analysis, the influence of the correction parameter is discussed, and a comparison is made between the original and the new phase-decoupled versions of SWAN through some typical examples of wave fields around semiinfinite breakwaters, breakwaters with gap, and detached breakwaters on different bathymetries. The results show that the new phase-decoupled model exhibits improvements in both numerical convergence and Prediction results for the case of a steep varying an extremely uneven sea bottom than the original one.

並列關鍵字

wave refraction-diffraction ； SWAN ； higher-order bottom slopes ； wave-current interaction ； rapidly varying sea bottom

參考文獻

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Holthuijsen, L. H., Herman, A., and Booij, N., “Phase-decoupled refrac- tion-diffraction for spectral wave models,” Coastal Engineering, Vol. 49, pp. 291-305 (2003).