Integrated modelling of the morphological evolution of the sand engine mega-nourishment

Integrated modelling of the morphological evolution of the sand engine mega-nourishment

Luijendijk, Arjen (TU Delft Coastal Engineering; Deltares)
Velhorst, R.L.C.
Hoonhout, B.M. (TU Delft Coastal Engineering; Deltares)
de Vries, S. (TU Delft Coastal Engineering)
Ranasinghe, Roshanka (Deltares; IHE Delft Institute for Water Education)

Aagaard, T. (editor)
Deigaard, R. (editor)
Fuhrman, D. (editor)

2017

This study presents some recent developments in coastal morphological modeling focusing on flexible meshes, flexible coupling between models operating at different time scales, and a recently developed morphodynamic model for the intertidal and dry beach. This integrated modeling approach is applied to the Sand Engine mega nourishment in The Netherlands to illustrate the added-values of this integrated approach. A seamlessly coupled modeling system for Delft3D and AeoLiS has been developed and applied to compute the first years of evolution of the Sand Engine, both for the subaqueous and subaerial areas. The subaqueous bed level changes have been computed with the new Flexible Mesh version of Delft3D, resulting in comparable accuracy levels as to the standard Delft3D version. The integrated morphodynamic prediction of both subaqueous and subaerial reveals a qualitative behavior which is very similar to observations. Model results confirm that after the first year after construction the sand supply for aeolian transports is predominantly from the intertidal area. The AeoLiS model results indicate a significant intertidal erosion volume of about 230,000 m3 over the five year period, which is a not to be neglected volume, especially in multiyear or decadal predictions. Interestingly, the model results show that the spit, developed by the wave-related processes, is also subject to aeolian transports acting on the emerged spit during lower tides. The seamlessly coupled models are now able to combine the dry beach behaviour with subaqueous morphodynamic evolution, which is important in medium-term to decadal morphodynamic predictions but also relevant for designing such sandy solutions incorporating lakes, lagoons, and relief.

morphodynamics
mega-nourishment
integrated modelling
dunes
Delft3D
AeoLiS

http://resolver.tudelft.nl/uuid:76f6b550-21f1-4c0d-830d-8d33d69291e4

Proceedings of Coastal Dynamics 2017: Helsingør, Denmark

Coastal Dynamics 2017, 2017-06-12 → 2017-06-16, Kulturværftet, Helsingor, Denmark

Institutional Repository

conference paper

© 2017 Arjen Luijendijk, R.L.C. Velhorst, B.M. Hoonhout, S. de Vries, Roshanka Ranasinghe