Development of Depth-averaged Water and Sediment Routing Mathematical Model for the Lower Yellow River

Geometric properties of the lower Yellow River can be summarized as narrow channel, broaden floodplain and the flow velocity and direction in it may changes suddenly before and after overflowing the main channel. Grids generation of lower Yellow River was discussed and a hybrid grids arrangement which composed of quadrilateral grids in main channel and triangle grids in floodplain was suggested to adjust the characters of the lower Yellow River and control the grid number within a reasonable range to reduce the calculation work load. At the same time, a depth-averaged water and sediment routing mathematical model was built and validated with Yellow River water and sediment regulation test data. The validation results indicate that the model established here works excellently and the calculated results are in good agreement with the observed ones.