The Application Of 2d Sediment Mathematical Model In Rongjiang Waterway Regulation

Because of the shallow water area, the depth of flow is insufficient for navigation, restricts the development of the port. Improving the navigable capability of waterway, it is necessary to study the changes of hydrodynamic condition and to predict the amount of sediment deposition in the dredged channel. In comparison with physical model and in situ observation of the dredged channel, mathematical model is characterized by short cycle, low cost and high efficiency. Therefore, it's valuable that mathematical model is used to predict flow variation and river-bed deformation. The sediment-laden capacity is a key parameter to the mathematical model of sediment transport, which is not well understood for the complexity of suspended sediment movement in the tidal estuary, so it's theoretically significant to study further the sediment-laden capacity of tidal flow.It is dependent on the systematic analysis of the developing history and the present situation of the sediment mathematical model in this paper. Based on the theory and equation of flow and sediment motion, a 2-D depth-integrated mathematical model for unsteady flow and sediment model in the Rongjiang River is developed by using FVM on triangle elements. The model will simulate the change of Rongjiang River's flow and sediment, study on the riding high tide lever and lowest navigable stage, and calculate the channel transit capacity form Jueshi Bridge to Ronghua Bridge.The main content of this paper includes the following items:â‘ Outlines of the situation of Rongjiang River, the existence information is adopted to carry on the qualitative fluvial process.â‘¡A 2-D depth-integrated mathematical model for unsteady flow and sediment model in the Rongjiang River is developed by using FVM on triangle elements. The result shows that the calculated tide lever, velocity and the predicted course of sediment concentration are closely fitted with the field data.â‘¢The model that has been established in this paper simulate dredged channel of the shallow water area. The calculate result shows that flow condition change is not significant difference before and after dredging, but the max velocity increase slightly. The erosion and deposition of Rongjiang River generally expressed as micro-washed and micro-silt.â‘£The existence tide information is adopted to calculate riding high tide lever along Rongjiang River. the basic formula of the channel transit capacity is use to calculate the theory transit capacity of Rongjiang River.???...