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

Delft3D-WAVE: Structured grid, nesting and domain decomposition

Ruairi MacIver, modified 5 Years ago.

Delft3D-WAVE: Structured grid, nesting and domain decomposition

Padawan Posts: 45 Join Date: 5/1/13 Recent Posts
The following are probably infantile statements but could someone confirm whether my understanding is correct.

1) Nesting sub-domains/sub-models wholly within a principal domain is the principle mechanism for creating regions with finer resolution for Delft3D-WAVE computations.

2) Nested domains/models do not feedback to the larger domain/model.

3) Although it is possible to create "bands" of finer resolution in a recti-linear structured grid, that is extending the full width of the grid horizontally or vertically [e.g. using the 'locally refine" function in RGFGRID], it is not possible to create containing a "block" region of finer resolution, that is extending for a part of the width. Presumably because of issues with M,N administration.

4) Domain decomposition is not applicable for Delft3D-WAVE computations (it is only applicable for Delft3D-FLOW computations).
Qinghua Ye, modified 5 Years ago.

RE: Delft3D-WAVE: Structured grid, nesting and domain decomposition

Jedi Council Member Posts: 612 Join Date: 3/2/11 Recent Posts
Hi Ruairi,

In general you are right. In Delft3D-WAVE, nesting is used. In Delft3D-FLOW, both nesting and domain decomposition may be used.

For the nesting technique in general, there is no feedback from the inside domain to the outside. It is one-way coupling.

For the domain decomposition, it is double-way coupling.

So far in Delft3D curvilinear grid, it is not applicable to have a "block" (as as you called) refinement, but only "band" (as as you called) refinement. In the Delft3D-Flexible mesh version, you can have various levels of refinement.

Hope this help a bit?

Ruairi MacIver, modified 5 Years ago.

RE: Delft3D-WAVE: Structured grid, nesting and domain decomposition

Padawan Posts: 45 Join Date: 5/1/13 Recent Posts
Hi Qinghua,
Thanks for confirming my understanding was largely correct.
I look forward to working with the Flexible Mesh version as it clearly more versatile. But ... will the WAVE module be adapted to use the Flexible Mesh approach as well?