Study on 3D Flow Structures and Bed Deformations in Curved Open Channels

Abstract

Bed deformations in river bends are crucial for river management. However, due to the complex flow structures, the prediction of bed deformations in river bends is difficult. In this study, flow structures and bed deformations in curved open channels are discussed through laboratory experiments and 3D numerical simulations. In the 3D model, RANS approach was adopted. The numerical results were compared with experimental data performed by Hinokidani (1998). It is indicated that the fundamental properties of both flow and bed deformation can be captured well by present computations. In addition, numerical and laboratory experiments were conducted for verifying the difference of bed deformation patterns depending on different channel and hydraulic conditions. The experimental results showed that bed deformation patterns in river bends closely depend on two dimensionless parameters; the Dean number and the depth over the curvature radius.