Numerical Modelling Of Sediments In Cork Harbour

"In recent years there have been considerable developments in the new and emerging field of hydroinformatics. This relatively new discipline is concerned with the application of computer and networking technology for the planning, management and protection of water bodies. Environmental issues in estuaries require accurate and detailed knowledge of cohesive sediment transport processes to assess different issues including water quality, pollutant dispersion, and dredging and maintenance of navigation channels. This thesis presents a review of the main sediment properties and processes required for modelling the behaviour and transport of sediments. It also introduces a new approach to sediment properties using fractal geometry. The primary cohesive sediment processes of deposition, erosion, flocculation and consolidation are reviewed. An overview of the concepts, approaches and steps involved in undertaking numerical modelling for water bodies is presented. The numerical model DIVAST is applied, A Graphical User Interface has been developed (DIVAST GFE) for this solfware package. It uses the latest software technology, DirectX Version 8 with Visual Basic 6.0. DIVAST GFE is available on the enclosed CD. This thesis models the behaviour and transport of cohesive sediments in Cork Harbour, Ireland. It investigates the main sediment transport patterns and behaviour, and also identifies local areas of sediment erosion and deposition. Model inputs include site bathymetry, and river and tidal flows. Model outputs include hydrodynamic conditions, suspended sediment plume concentrations and identification of local areas of sediment erosion and deposition. Calibration and verification of the Cork Harbour model was successfully undertaken by varying the bed roughness and eddy viscosity coefficient. Model simulations were undertaken for different conditions including varying the tidal inputs, river inflows, and floe sizes. The results yield information on sediment dynamics within the Cork Harbour system including suspended sediment concentrations, areas of erosion and deposition and depositional mass loading rates. Model results suggest that tidal inputs have the greatest influence on overall sediment patterns."