Development of an Integrated Free Surface and Groundwater Flow Model

The main target of this book is to prepare a general integrated two-dimensional, numerical groundwater-surface flow model, which could be applied to different applications. For free surface flow modelling, an existing widely used 2-D, unsteady mathematical model, named the DIVAST (Depth Integrated Velocities And Solute Transport model, developed originally by Falconer 1976) model has been refined. However, in order to simulate the flow and solute transport in porous media, a two-dimensional model namely the GWK (Ground Water Key) has been developed to include an aquifer influenced by tidal currents. The GWK model predicts the water table, the velocity components in the horizontal plane, the recharge/discharge levels for source/sink on the water table and solute tracer levels across the domain. The structure of the GWK model is based on having a good relationship with the free surface flow model. A physical scale model, based on the Fleet Lagoon and adjacent coastal waters, UK, has been constructed to provide experimental data of the groundwater transport between an idealised wetland and the adjacent coastal waters. The integrated model has been verified using the laboratory data.