Servizio Comunitario di Informazione in materia di Ricerca e Sviluppo - CORDIS

Mathematical modelling of flow, water quality and sediment transport rate in coastal, estuarine and rivers.

Mathematical models of flow, water quality and sediment transport rates in coastal, estuarine and river waters have been developed.

As a major part of the project, emphasis has been focused on developing a novel and computationally efficient 3-dimensional numerical model for predicting flow and solute transport processes in basins where the nonlinear terms may dominate. The model is based on the solution of the 2-dimensional depth integrated equations of motion in the first instance, with the implicitly evaluated water surface profile then being included in a 3-dimensional layer integrated model to close the equations for solution of the layer averaged velocity field. The model developed is second order accurate and requires no limitation on the time step size for wave stability. However, for accuracy requirements the Courant number is generally restricted to about 8. The model has been applied to several studies, including: tide induced circulation in a rectangular harbour tidal current distributions in Masan Bay, Korea and tidal currents and suspended sediment fluxes in the Humber Estuary.

In refining the 2-dimensional numerical model DIVAST (depth integrated velocities and solute transport), a number of significant developments have been made to the model. In particular, these include: refined representation of the complex hydrodynamic processes of tidal flooring and drying, with this refinement leading to more accurate predictions than those produced using other models documented in the literature; an efficient higher order accurate treatment of pronounced concentration gradients, leading to bounded and more accurate predictions of concentrated distributions from long sea outfalls; a higher order accurate treatment of the advective accelerations, leading to an improved representation of tidal eddies; and a dynamically linked nested model, including a unique full inclusion of the advective transport terms at the coarse to find grid interface. In undertaking these model refinements, the model has been applied to 4 studies, namely: Poole Harbour, United Kingdom (UK); Bridlington outfall, UK; the Humber Estuary, UK; the Yangtse Estuary, China.


R A FALCONER, (Hyder Professor of Environmental Waste Management)
Tel.: +44-1222-874280
Fax: +44-1222-874597