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

Boundary doubt

Teresa Juarez, modified 7 Years ago.

Boundary doubt

Youngling Posts: 4 Join Date: 8/29/12 Recent Posts
To whom it may concern,

I´m new on Delft3d model. I´m working with FLOW module trying to simulate a semidiurnal flow. While I was having some issues, I decided to work with a simple box model, just to be sure what I´m doing is correct. The small box figures a bay and the big one the ocean. The line is a forced boundary (Water Level - Harmonic) and the dashed line is a closed boundary (Figure attached). Right now I have expanded the ocean area to avoid the edge noise.

The closed boundary at the bay is ok, however I would like to represent the east & west boundary as open with absorbing conditions (sponge).

I read the manual but I´m a little confused on how to set up the boundary combination.

Can any one assist me??

Thanks and regards
Teresa V.


Renan Ribeiro, modified 7 Years ago.

RE: Boundary doubt (Answer)

Padawan Posts: 55 Join Date: 3/23/11 Recent Posts
Hi Teresa,

You can try to use Neumann boundary conditions at both sides.
This type of boundary you impose a water level gradient, then you set it to 0.

Teresa Juarez, modified 7 Years ago.

RE: Boundary doubt

Youngling Posts: 4 Join Date: 8/29/12 Recent Posts
Thank you very much Renan!
It works pretty good.

Even it is written in the FLOW manual, I still don´t figure how does this combination works. Would you have time to briefly explain me? I wouldn´t like to work as a black box testing.