REVISITING THE JONSWAP BOTTOM FRICTION FORMULATION

[摘要] The derivation of the JONSWAP bottom friction for wind-driven seas is revisited. This is motivated by the fact thatin the literature two different values for the corresponding coefficient are recommended, one value applicable forswell conditions and a significantly higher value for wind-driven sea conditions. The value applicable for winddrivenseas was originally determined by Bouws and Komen (1983) who studied the source term balance of aremarkably stationary storm in shallow water. We used a more accurate interpretation of these observations byhindcasting this storm with the third-generation wave model SWAN. In addition, we compare wave model resultswith measurements in the Wadden Sea and with parametric growth curves, some of which were obtained in LakeGeorge, Australia. The results strongly suggest that the lower bottom friction value of Cb=0.038 m2s-3 is applicablefor both wind-sea and swell conditions.

[学科分类] 建筑学

[关键词] Wave modelling;bottom friction;TMA scaling;SWAN;JONSWAP;North Sea