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 introduced by Holthuijsen et al.  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.
"AN IMPROVEMENT OF WAVE REFRACTION-DIFFRACTION EFFECT IN SWAN,"
Journal of Marine Science and Technology: Vol. 21:
2, Article 12.
Available at: https://jmstt.ntou.edu.tw/journal/vol21/iss2/12