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

RE: Making Flow Direction Map using QUICKPLOT/GPP

Ali Rezaie, modified 5 Years ago.

Making Flow Direction Map using QUICKPLOT/GPP

Youngling Posts: 14 Join Date: 3/13/13 Recent Posts
Dear all,

I'm working as a Research Associate at IWFM,BUET,Bangladesh. We have been using Delft 3D 3.28 flow module for the estuarine systems of Bangladesh where we want to show the flow circulation pattern and directions at one tidal period or during neap or spring tide. Since our grid is fine with about 400m spacing, the velocity vector shows the arrow for every 400m. But we need to draw a map or image where we will simply show the change in direction within every 1km (or more) disctances.

My question is, is it possible to draw such map using QUICKPLOT or GPP ? If yes, then how can we do this or where we could find the exact information rather than reading the whole manual ?

Thank you in advance.

Regards
Rezaie
Richard Measures, modified 5 Years ago.

RE: Making Flow Direction Map using QUICKPLOT/GPP

Jedi Knight Posts: 178 Join Date: 3/23/11 Recent Posts
Hi Ali,

In QUICKPLOT one simple way to reduce the number/density of velocity vector arrows is to select either 'uniform' or 'distance' from the 'Field Thinning' options (these are available in a drop down menu on the right hand side of the QUICKPLOT GUI once you have selected a depth averaged velocity or some other vector parameter.

Uniform field thinning allows you to subsample the arrows uniformly e.g. settting Factor = 2 would display arrows on a 800m grid rather than 400m grid in your example.

Distance field thinning tries to display arrows on a regular spacing (in metres). This is useful if you have a irregular grid cell sizes but want to display arrows at similar spacing everywhere.

More powerful options for displaying vector arrows are available using the Matlab open earth tools.

Happy new year!

Richard
Ali Rezaie, modified 5 Years ago.

RE: Making Flow Direction Map using QUICKPLOT/GPP

Youngling Posts: 14 Join Date: 3/13/13 Recent Posts
Dear Richard,

Thank you for your help. I found it and successfully used it to delineate the flow direction over estuarine system of Bangladesh.

Do you have any idea about nesting models ? or DD boundary ??

I need to refine the grid locally over the rivers and keep coarser grid at ocean.

Thanks Again !


Regards
Rezaie
Research Associate
Espadelta Grant Consortium
IWFM, BUET
Richard Measures, modified 5 Years ago.

RE: Making Flow Direction Map using QUICKPLOT/GPP

Jedi Knight Posts: 178 Join Date: 3/23/11 Recent Posts
Hi,

Glad you managed to work out the vector arrow spacing in quickplot.

I've used DD in a model before but only once so I'm far from an expert. I can't remember the details but by following the instructions in the FLOW and RGFGRID manuals I managed to get it working without too many problems. I created my grid by starting with one grid covering the whole area at the lower resolution then making a copy of it. In the first copy I deleted the area I wanted to be high resolution and in the second I deleted the low resolution area. I then refined the high resolution area and made the DD join. Can't remember much else useful I'm afraid. If you run into specific problems others might be able to help.

I've never done a nested model in D3D so can't provide advice on this.

Good luck,

Richard
Ali Rezaie, modified 5 Years ago.

RE: Making Flow Direction Map using QUICKPLOT/GPP

Youngling Posts: 14 Join Date: 3/13/13 Recent Posts
Hi Richard,

One of my team mates found out the nesting process and we running our nested models now. Lets see what happens!

Currently we are applying Deflt3D over the coastal regions of Bangladesh and have Bay of Bengal up to the Swatch of No ground as the downstream location. I hope nesting would solve few major problems.

Do you have any experiences in working on storm surge model using Delft 3D, to be specific about space varying wind data ?

Many Many thanks again !

Regards
Rezaie
Richard Measures, modified 5 Years ago.

RE: Making Flow Direction Map using QUICKPLOT/GPP

Jedi Knight Posts: 178 Join Date: 3/23/11 Recent Posts
Hi Rezaie

Glad you managed to get nesting up and running. I've not got any experience working with spatially varying winds - sorry.

Richard
Ali Rezaie, modified 5 Years ago.

RE: Making Flow Direction Map using QUICKPLOT/GPP

Youngling Posts: 14 Join Date: 3/13/13 Recent Posts
Richard,

Thanks for your reply. I will post here If I find any solution on " Space varying wind and pressure " data format.

Rezaie