Author(s): T. Uchida; S. Fukuoka
Linked Author(s):
Keywords: series of submerged groins; Bottom velocity; Horizontal vorticity; Local scouring; Non-equilibrium bed load; Bed tractive force
Abstract: A practical numerical bed variation method for evaluating various functions of groins in rivers is required. The 2D method is inadequate to simulate local scouring around structures due to 3D flow. On the other hand, full 3D turbulence methods are still limited for applications to floods in natural rivers. Therefore, a refined depth integrated method is required for the practical use. In this paper, the Bottom Velocity Computation (BVC) method is developed to evaluate velocity acting on sediment particles effectively. In the BVC method, depth-integrated horizontal vorticity and water surface velocity equations are computed simultaneously with shallow water equations. To compute bed variation around submerged groins, evaluation methods for non-equilibrium bed load and bed tractive force by using bottom velocity is adopted. The adequacy of the method is discussed through the comparisons with the laboratory experimental results in a channel with a series of submerged groins.
Year: 2011