ABSTRACT
The aim of this work is the application of a 2D depth-averaged URANS simulation model to study the resonant coupling between standing gravity waves and vortex shedding in shallow water cavity flows. The URANS turbulence modelling approach is adopted for this purpose thanks to the particularities of these turbulent shallow flows: they are characterized by large scale horizontal eddies (2D), which coexist with small-scale 3D turbulence. The proposed model uses a high-resolution WENO-ADER numerical scheme, which allows to accurately resolve the large 2D eddies with a low numerical diffusion and dispersion. The small-scale 3D turbulence cannot be resolved by the 2D depth-averaged URANS, hence it is modelled using a closure relation. Experimental data recorded in straight channels with lateral cavities is considered as benchmark. The ability of the model to predict the resonant gravity waves observed in the experimental setup is assessed. Furthermore, the numerical results are not only analyzed in the physical domain (i.e. space and time) but also in the frequency domain. The study of the spectral characteristics of the time evolution of the water surface and vorticity allows to obtain 2D maps of the seiche amplitude and coupling intensity.
