ABSTRACT:
This paper describes the validation of a numerical hydraulic model which uses a
finite difference method for modelling unsteady free surface water flow over
common hydraulic structures. The numerical hydraulic model is based on the Saint
Venant equations (SVES) using a staggered finite difference scheme to evaluate the
discharge, the water stage, and the cross section area within the domain. While the
Modified Method of Characteristics (MMOC) is applied to achieve open boundary
downstream and overcome the problem of reflections there. A series of simulations
are compared against an existing set of experimental data and other models for the
free surface flow over a broad-crested weir. The developed model is promising and
capable of simulating different cases of water flow that contain both steady and
unsteady flow. This model could be used as a stepping stone for different purposes
including parameter identification (Ding et al. 2004), Flood risk assessment
(Elhanafy and Copeland 2007) ,uncertainty in the predicted flood (Elhanafy and
Copeland 2007) and (Elhanafy et al. 2007).