Analisi dinamica-morfologica dei corsi d'acqua pseudo meandriformi mediante modelli a fondo mobile

In the last years in river engineering, the numerical models that simulate both fluvial hydraulics and sediment transport, have been used and developed in order to provide an accurated representation of morphological phenomena (mobile bed models). These models allow the simulation of the bed level change, the hydraulic profile, the mean velocity and the streaming lines corresponding to a short flood wave. These models, if used in long-term hydrological events, can provide useful information about fluvial morphological tendency and its temporal variation for different boundary conditions. In the present thesis work, several numerical simulations of a short flood wave (return period equal to 20 years) on the Torre river are performed to obtain a sensibility analysis by using the hydro-morphological bi-dimensional MIKE 21C model. The sensibility analyses have been carried out in order to establish the dependency of the model from the main parameters. Moreover a comparison between the simulations of MIKE 21C with those carried out using other two models, HEC-RAS (1D model) and CCHE2D (2D model), is carried out. The results show the better performance of the 2D model in the computation of the morphological variation of gravel bed rivers.