An efficient numerical model for meandering rivers in the orthogonal curvilinear coordinates;

To analyze the feature of dam-break flow in natural channel bends,channel-fitted orthogonal curvilinear coordinate system is established and two-dimensional shallow water equations are derived in this system through coordinate transformation,simplification and depth integration.

The results indicate that flow field in the bends of tidal estuary differs obviously from that in the bends of non-tide river,including the downstream increase of velocities in the estuarine bends,the bifurcation of mai.

On the basis of the successful experience in studing navigable technique of Xiangjiang River Dayuandu Navigation Complex,the paper discussed the layout principle of the bend reach navigation complex,the optimization pattern of the training mole structure as well as the siltation features at approach channel of the shiplock and its minimixing measures.

A finite element, method was adopted for weighted convergent mass establishing 2-D flow mathematical model in flow simulation of channel bends, by which the flow pattern of middle and lower channel bends of Li River in the discharge of water transportation was simulated and the calculated results of which concerning water level, flow velocity and discharge were coincident well with measured data.

In this paper, the bed form laws in channel bends are investigated.