Author(s): Shinichiro Onda; Takashi Hosoda; Yoshizumi Ishibashi
Linked Author(s): Shinichiro Onda
Keywords: Dunes; Transition processes; Flow resistance; Boussinesq equation and non-equilibrium sediment transport model
Abstract: Over erodible bed, various sand waves are formed in response to hydraulic and bed conditions, and flow resistance changes with the development and attenuation of such sand waves. In this study, hydraulic experiments are firstly carried out to examine the development and transition processes of dunes. Then, a numerical model to reproduce the transformation of dunes under unsteady flow conditions is developed by combining a depth averaged flow model incorporating the effects of vertical acceleration and a non-equilibrium sediment transport model. To verify the numerical model, the calculated results are compared with the results of experiments, and the applicability of model is assessed by examining the temporal changes of water depth, wave length and wave height.
Year: 2010