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. 
 

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

 

 

Message Boards

Particle Tracking

Francesco Enrile, modified 2 Years ago.

Particle Tracking

Padawan Posts: 26 Join Date: 3/25/12 Recent Posts

Is it possible to use the module particle tracking with a spherical grid?

AM
Arjen Markus, modified 2 Years ago.

RE: Particle Tracking

Jedi Knight Posts: 223 Join Date: 1/26/11 Recent Posts

In principle yes, that is possible. The one thing I do not know by heart is whether the grid distances and surface areas are converted correctly to meters and square meters instead of degrees and square degrees. Unfortunately I have no time today to dive into that, but the crucial point would be to see what the grid coordinates are if you view the grid via the LGA/CCO files, as that is where Delft3D-PART gets its geometrical information from.

You can visualise the grid in these files via QuickPlot. Check the range, that ought to indicate whether the grid contains the coordinates in meters or degrees.

Another thing though: the use of spherical coordinates suggests that your model covers a substantial area. You may need to use a large number of particles (in the order of millions) to cover that area with sufficient accuracy.

Francesco Enrile, modified 2 Years ago.

RE: Particle Tracking

Padawan Posts: 26 Join Date: 3/25/12 Recent Posts

If I open lga/cco files the x and y coordinates show lon/lat values. I compiled Delft3D tag 7545 on linux with gfortran. When I launch Deft3D-PART I get the following message:

 

 

  WARNING: Your x-coordinates are in the range [-180,180] and your
           y-coordinates are in the range [-90,90]. You might have
           a spherical grid. This is not yet supported by PART.

 

I imagine that I must convert my spherical grid in a cartesian one.

AM
Arjen Markus, modified 2 Years ago.

RE: Particle Tracking

Jedi Knight Posts: 223 Join Date: 1/26/11 Recent Posts

I was unaware that Delft3D-PART actually checks for that :). Yes, like I said the problem is that it derives its geometry directly from the LGA/CCO file and as long as that is given in meters, all should work. Converting the model to a cartesian one will get around this.