Abstract
A quasi-three dimensional numerical model for flood flows was developed. The governing equation with the effect of secondary flow on the momentum equation was used in the model. The velocity profile of secondary flows proposed by Engelund(1974) was used. The model is based on finite volume method using HLL (Harten, Lax and van Leer(1983)) numerical flux, which is one of a Riemann solver. The model is verified against two experimental data of flows in curved channel and in river confluence. It shows that the model can reproduce the complex behavior of the flows with reasonable accuracy.
