Mathematical modelling for an unsteady vertically stratified flow field

The development of a mathematical model to simulate an unsteady stratified flow field by utilizing the momentum equation, the continuity equation, and the mass transport equation as the governing equations of the model is described. This model is developed based on a hypothetical river estuary system consisting of a main channel and a branch channel. The unsteady flow is simulated by a tidal motion as one of the boundary conditions and the suspended sediment concentration is utilized as an indicator of stratification. The total depth of water of the model channel system is divided into layers of equal thickness. The model first calculates the hydrodynamic characteristics of each layer of the river estuary. Then by utilizing the information from the hydrodynamic calculation, it computes the transport of suspended sediment in each layer.