Comparison of turbulence models for stage-discharge rating curve prediction in reach-scale compound channel flows using two-dimensional finite element methods

This paper attempts to assess the accuracy of constant eddy viscosity, Elder and k-epsilon turbulence models in the numerical simulation of reach-scale compound channel flows using two-dimensional (213) finite element methods. Assessment was conducted using benchmark stage-discharge data collected from straight and meandering compound channel configurations at the UK Engineering and Physical Science Research Council (EPSRC) Flood Channel Facility, For mesh resolutions and topologies used in reach-scale studies, all models were found to be adequate predictors (20% error). Also, sensitivity of the turbulence parameter calibration with respect to the predicted flow depth showed that the constant eddy viscosity model's performance can be highly dependent on the choice of turbulence parameter value. (C) 2002 Elsevier Science B.V. All rights reserved.