Diffusion-Wave Flood Routing in Channel Networks

Abstract

A nonlinear diffusion-wave model is developed for routing of floods in dendritic open-channel networks. The model considers backwater effects from both upstream and downstream ends of a channel. An overlapping-segment technique is adopted to decompose the network. The nonlinear algebraic finite-difference equations are solved through a special formulation of tridiagonal banded matrices. Comparison of the results of the proposed model to those of the dynamic-wave and nonlinear kinematic wave models indicates that the proposed model is nearly as accurate as, and computationally much cheaper, than the dynamic-wave model. It is computationally as inexpensive but more accurate than the nonlinear kinematic-wave model.