基于有限体积法及FDS格式的感潮河段二维泥沙冲淤模型

本文以木兰溪下游裁弯河段为例，建立了有限体积法的水平二维非恒定流均匀沙不平衡输移计算模型。采用黎曼近似解通量差分裂(FDS)格式计算通过各单元边的水流、含沙量法向数值通量，并应用相关的悬移质、推移质河床变形计算公式计算冲淤变化。数值模型经相应的河工模型试验资料率定、检验后，预测了裁弯工程建成后河道可能的冲淤变化，为工程设计和施工提供依据。

A 2D sediment transport model based on the FVM with FDS for tidal rivers

A depth-averaged two-dimensional unsteady flow with uniform non-equilibrium sediment transport model is proposed to simulate the riverbed deformation in a tidal river. The equation system in the model is discretized by finite volume method (FVM). The flux difference splitting (FDS) algorithm, an approximate Riemann solver, is employed to estimate the normal fluxes across the interface of cells. The sediment concentration is obtained simultaneously with the flow part. Sediment conservation law determines the bed variations caused by suspended load and/or bed-load. The model has been verified by experiments conducted in a movable-bed physical model. The comparison between simulated results and experimental measurements shows good agreement. Model has been applied to a cutoff plan for the meandering tidal river Mulan.