Author(s): Yuki Kajikawa; Osamu Hinokidani
Linked Author(s):
Keywords: Slit sabo dam; Numerical simulation; WENO scheme; Sedimentation; Sediment flushing
Abstract: In this paper, a depth-averaged two-dimensional numerical model for flow and bed deformation with nonuniform sediment is presented in order to estimate sediment transport around a sabo dam with a slit. In the numerical model, the Cartesian coordinate system is adopted, and the Fractional Area/Volume Obstacle Representation (FAVOR) method, which has the ability to impose boundary conditions smoothly at complex boundaries, is introduced into the governing equations in consideration of applying the estimation to actual rivers with complex topography. Moreover, the fifth-order weighted essentially non-oscillatory (WENO) scheme, which is a shock-capturing scheme, is applied to discretization of the convection terms of the governing equations. In order to verify the validity and applicability of the model, it is applied to laboratory experiments of bed deformation concerning the sedimentation process and the sediment flushing process in a slit sabo dam. Comparisons between the simulated and experimental results show that the model reproduces both processes with sufficient accuracy. In particular, the model can reproduce the formation of bleeding channels in the sediment flushing process. Moreover, by applying the WENO scheme, we show that the model is able to calculate flow and bed deformation stably without numerical oscillations.
Year: 2013