Comparison of turbulence models in the turbulent wave boundary layer for cnoidal waves

Turbulent structures in the bottom boundary layer beneath the wave motion have an important role in the nearshore sediment transport modeling and its analyses. Cnoidal waves can be used as a representative of asymmetry waves in the ocean. This paper is aimed to observe the structure of turbulent boundary layer under cnoidal waves as a representative of asymmetry waves in which the effect of asymmetric is actualized along wave cycle related with the wave asymmetric parameter, Ni. The turbulent boundary layer characteristics beneath cnoidal waves motion (i.e. mean velocity and turbulent intensity) are given in the results of experimental results and turbulent numerical models (i.e. the k-ε, the k-ω, the BSL k-ω and the SST k-ω model). Turbulent properties prediction of cnoidal waves from each turbulence model is compared among them and that of experimental results. A laser Doppler velocimeter (LDV) is used to measure the profiles of velocity distribution in the tunnel of oscillating wind over rough bed beneath cnoidal waves motion. From the comparison of the average velocity distribution between all the models of turbulence and the results of experimental for the cases of cnoidal waves in general, it has been obtained that the model of BSL k-ω is superior to predict which is followed by the model of k-ε, the model of k-ω and the model of SST k-ω.