Prediction of cohesive sediment transport and bed dynamics in estuaries and coastal zones with integrated numerical simulation models (COSINUS)

Abstract

The goal of the COSINUS project, executed from October, 1997 through September, 2000 was to contribute to the development of an integrated sediment transport management model. Integrated refers to the integration of all relevant physical processes over the entire water column and the sediment bed and their interactions. COSINUS covers the theoretical, experimental, and numerical study of the interaction of the processes, which play a crucial role in the flocculation of sediment particles, the interaction between suspended sediment and turbulent flow, the generation and maintenance of concentrated near-bed suspensions (including lutocline formation), and the transition between fluid mud and the sediment bed. The state-of-the-art knowledge on cohesive sediment transport showed that there was still a lack of experimental data on the role of flocculation and turbulence in the formation and erosion of mud beds and on the formation of CBS (concentrated benthic suspensions, or “fluid mud”). Therefore, an experimental programme was set up to obtain these data. It consisted of field measurements in the Tamar estuary on floc formation and laboratory experiments on formation and erosion of mud beds and CBS, and the influence of floc structure and turbulence on these processes.