PREDICTING FLOW IN CURVED OPEN CHANNELS BY DEPTH-AVERAGED METHOD

A depth-averaged model formulated in the Cartesian coordinate system is introduced for simulating the velocity distribution in curved open channels. The finite element method is used to simplify the geometry problems in practical cases such as irregular cross sections and channels of varying plan curvature. The mathematical model consists of the depth-averaged continuity equation, the momentum equations, and two moment-of-momentum equations for closure purposes. The numerical analysis predicts satisfactory depth-averaged longitudinal and transverse velocities as well as reasonable secondary flows. The comparison of the numerical predication and the experimental results is included. The mathematical model discussed here can be applied to other channel flow problems where secondary flow and its effects are important.