Stage-discharge prediction in straight compound channels using 3D numerical models
Date
2013
Authors
Conway, P.
O'Sullivan, J.
Lambert, M.
Editors
Advisors
Journal Title
Journal ISSN
Volume Title
Type:
Journal article
Citation
Proceedings of the Institution of Civil Engineers: Water Management, 2013; 166(1):3-15
Statement of Responsibility
Philip Conway, John James O'Sullivan, Martin Francis Lambert
Conference Name
Abstract
An improved approach for applying three-dimensional (3D) computational fluid dynamics (CFD) models to estimate uniform flow stage–discharge relationships and velocity distributions in straight compound channels is presented. Commonly used modelling approaches tend to be over-specified. For a given flow and water level, desired results are obtained through calibration of resistance coefficients that can be artificially high and vary with changing flow conditions. Furthermore, the momentum interaction at the main channel–floodplain interface is sometimes ignored or is accounted for using a constant eddy viscosity. This potentially results in an overestimation of conveyance capacity in compound channels. The proposed approach represents an advance on these methods and uses a 3D CFD model with k–ε turbulence closure in a predictive capacity where a flow together with physically realistic resistance coefficients are specified. Downstream water levels are then iteratively adjusted until uniform flow conditions are established in the channel. The approach is validated against benchmark experimental data obtained from the large-scale UK Flood Channel Facility and is compared with predictions from divided channel methods.
School/Discipline
Dissertation Note
Provenance
Description
Access Status
Rights
Copyright status unknown