intro story Coast / Estuary

Coast / Estuary

Coastal systems are among the most dynamic physical systems on earth and are subject to a large variety of forces. The morphodynamic changes occurring to coastlines worldwide are of great interest and importance. These changes occur as a result of the erosion of sediments, its subsequent transport as bed load or suspended load, and eventual deposition. 
Estuaries are partly enclosed water bodies that have an open connection to the coast. Estuaries generally have one or more branching channels, intertidal mudflats and/or salt marshes. Intertidal areas are of high ecological importance and trap sediments (sands, silts, clays and organic matter).
Within the Delft3D modelling package a large variation of coastal and estuarine physical and chemical processes can be simulated. These include waves, tidal propagation, wind- or wave-induced water level setup, flow induced by salinity or temperature gradients, sand and mud transport, water quality and changing bathymetry (morphology). Delft3D can also be used operationally e.g. storm, surge and algal bloom forecasting. 
On this discussion page you can post questions, research discussions or just share your experience about modelling coastal and/or estuarine systems with Delft3D FM. 




Sub groups
D-Flow Flexible Mesh
Cohesive sediments & muddy systems



Message Boards

Relation between grid cell size in Nesting

Angela T P, modified 3 Years ago.

Relation between grid cell size in Nesting

Youngling Posts: 4 Join Date: 1/18/16 Recent Posts
Hello everybody,

I am working with 2 nested grids and I am wondering if is there any restriction about grid cell size between both grids?. I mean, cell grid size (in finer one) should be between 1/3- 1/5 of cell grid size in coarser one?
I use this relation when I work with ddboundaries, but I dont know if I have similar restrictions with Nesting.

Thank you!
Angela T P, modified 3 Years ago.

RE: Relation between grid cell size in Nesting (Answer)

Youngling Posts: 4 Join Date: 1/18/16 Recent Posts
I obtained this response from Deltares. In the hope that it could be helpful for someone:

It is not necessary to use the same ratio each time when nesting, but a 500 m to 30 m nesting ratio may a bit too much. You could include for example a 100 meter intermediate grid. But then again, if the results from the 500-30 simulation are the same as the results from the 500-166-55-30 simulation, then there may not be a problem. It depends a bit on how large the 30 meter grid is. On the offshore boundary, the 500 to 30 nesting may go just fine, but on your lateral boundaries near the coast, some issues may arise.

Thank you very much!