Numerical Simulation of the Tidal Flow and Suspended Sediment Transport in the Qiantang Estuary

Abstract

Results from a numerical modeling study are presented to investigate the tidal elevations, tidal current velocity, bed deformation, and suspended sediment concentration in the Qiantang Estuary, China. The Qiantang Estuary is well-known for its macrotide, which generates a hydrodynamically complex environment. This presents challenges for numerical modelers to accurately simulate the flow field and sediment transport in the region. This paper presents a mathematical model using finite volume method with unstructured mesh to simulate the tide-induced water elevation, current velocity, bed deformation, and suspended sediment transport in the Qiantang Estuary. The parameters in the model were determined using the long-term observed field data of the Qiantang Estuary. The simulated tidal elevations and current velocities agree well with the field observations. The numerical prediction of the bed deformation in 5 months is reasonably compared with the field measurements carried out in the same period. However, relatively large deviations exist between the simulated and observed suspended sediment concentrations, which are discussed in this paper.