Wave setup properties in the surge-wave coupled simulation: a case study of Typhoon Khanun

The accurate prediction of surge height is vitally important in designing coastal defense structures. With the advancement of computation efficiency, many researchers have studied the wave-current interaction on surge height by coupling hydrodynamic and wave models. In this study, Deflt3D Flow model was interacted dynamically with Delft3D Wave model to simulate the storm surge process caused by typhoon Khanun to obtain the spatiotemporal properties on wave setup induced by storm wind. Simulations with and without wave model have been conducted, revealing that the spatiotemporally varying wave setup distribute along the coastal line when typhoon is in the open sea with large wave height and surge height around. The spatial distribution of nearshore wave setup at landfall moment was obtained. Nevertheless the contribution of wave effects on storm surge increases slightly under intensive storm wind, with the maximum wave setup near typhoon center accounting for 10% of the peak surge height.