Author(s): Shinichiro Onda; Ryoya Inaba; Takashi Hosoda
Linked Author(s): Shinichiro Onda, Takashi Hosoda
Keywords: Antidunes; Numerical simulation; Sediment transport; Migrating direction
Abstract: Corresponding to hydraulic condition, various types of micro scale sand waves form over a sand bed and flow resistance is changed in the development or transition processes of sand waves. Consequently, prediction of flow resistance is of great importance in river engineering. In this study, formation process of antidunes is simulated by coupling the 3D flow model which solves simultaneously surface and seepage flows in the Cartesian coordinate and equilibrium sediment transport model. Water surface variations are calculated by using the density function method, and porous media approach is applied to simulate both surface and seepage flows. The numerical model is applied to the previous experiments by Inoue et al., and the characteristics of water surface and sand waves, and migrating direction are examined. The numerical model can simulate the development process of antidunes from the flat bed, and the downstream migration of antidunes can be reproduced reasonably, by considering the effect of seepage flow.
Year: 2020