Laboratory observations and numerical simulations of shoaling surface gravity waves

The present study aims at investigating some of the processes affecting shoaling waves in shallow water, with particular attention paid to the non-linear interactions between triplets of waves (triad interactions) and depth-induced breaking. Four monodimensional non-linear wave models (two phase-resolving and two phase-averaged spectral models) have been implemented and compared to laboratory experiments performed in a wave flume of the Laboratoire National d'Hydraulique (LNH). Tests were realized in breaking and non-breaking wave conditions. The non-linear mechanisms associated with the models are found to satisfactorily reproduce, both qualitatively and quantitatively, the wave spectra evolution along the bathymetric profile. The non-linear coupling effects are characterized by strong energy transfers between the interacting components of the wave field, and for some test-cases, by an important decay of wave energy.