Author(s): P. Rameshwaran; P.S. Naden

Linked Author(s):

Keywords: Free surface flow; meandering channel; river flow; three-dimensional models; turbulent flow

Abstract: This paper presents a three-dimensional numerical study for the calculation of turbulent free surface flow in a meandering channel. The flow calculation is performed by solving the three-dimensional Reynolds-averaged continuity and Navier-Stokes equations with the k-ε turbulence model for steadystate flow. The model equations are solved numerically with a general-purpose finite-volume code. A free surface treatment for the spatial variation of the water surface in meandering open channel flow is employed. The effect of mesh resolution on the solution is also investigated. The performance of the model is assessed by comparing predicted results with the large-scale high-quality experimental data obtained from the UK Flood Channel Facility for inbank flow. The predicted distributions of water surface elevation, bed shear stress and streamwise and transverse velocities are used to investigate model performance. The predictive ability of the model is also assessed against the simulations with a planar surface assumption and use of the surface porosity method with regard to the distribution of bed shear stress. The results show that the free surface treatment for ihe spatial variation of the water surface is vital for the accurate prediction of bed shear stress.

DOI: https://doi.org/10.1080/00221686.2004.9628314

Year: 2004