intro story D-Flow FM

 

D-Flow Flexible Mesh

D-Flow Flexible Mesh (D-Flow FM) is the new software engine for hydrodynamical simulations on unstructured grids in 1D-2D-3D. Together with the familiar curvilinear meshes from Delft3D 4, the unstructured grid can consist of triangles, pentagons (etc.) and 1D channel networks, all in one single mesh. It combines proven technology from the hydrodynamic engines of Delft3D 4 and SOBEK 2 and adds flexible administration, resulting in:

  • Easier 1D-2D-3D model coupling, intuitive setup of boundary conditions and meteorological forcings (amongst others).
  • More flexible 2D gridding in delta regions, river junctions, harbours, intertidal flats and more.
  • High performance by smart use of multicore architectures, and grid computing clusters.
An overview of the current developments can be found here.
 
The D-Flow FM - team would be delighted if you would participate in discussions on the generation of meshes, the specification of boundary conditions, the running of computations, and all kinds of other relevant topics. Feel free to share your smart questions and/or brilliant solutions! 

 

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We have launched a new website (still under construction so expect continuous improvements) and a new forum dedicated to Delft3D Flexible Mesh.
Please follow this link to the new forum: 
/web/delft3dfm/forum
Post your questions, issues, suggestions, difficulties related to our Delft3D Flexible Mesh Suite on the new forum.

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

 

Message Boards

Curvilinear Grid - Define spectral files

U
Joao Morim do Nascimento, modified 7 Years ago.

Curvilinear Grid - Define spectral files

Hello,

I have been working with DELFT3D during the last couple of months, however, I have had some issues about how to settle my spectral boundary files on a curvilinear grid. My spectral files are time series of directional wave spectra (as attached), which I would like to upload along my curvilinear boundary. I have read the manual hundreds of times, however, I still cannot get it.

For this type of grid should I use orientation, grid coordinates or grid cells?and how can I define the location of my files along my boundary, when using orientation, grid coordinates and grid cell?Honestly, the manual is very scarce and do not provide a clear understanding of how to do this.

Each one of my spectra files has already a location on top (as attached), however, I am convinced that DELFT3D does not take it into consideration as the user still needs to define the desired location along the boundary (boundary menu).

'Distance from corner point
It is the distance from the rst point of the side or segment to the point along
the side or segment for which the incident wave spectrum is prescribed. Note
that these points do not have to coincide with grid points of the computational
grid. Distance from corner point is the distance in [m], not in grid steps. The
values should be given in ascending order. The length along a side is measured in
clockwise or counter-clockwise direction depending on the option Wave angle (see
below). In case of a Segment option the length is measured from the indicated
begin point of the segment.'

How can i measure the distance between the corner point of my curvilinear grid until the location that I am specifying the spectra if my grid is curvilinear (I cannot get it).

I have ran a rectangular grid and it worked fine, which proves that my files are performing well. I just need to make those files work on a curvilinear grid to include additional displaced points.

Thank you very much, I really appreciate your time!

Attachments:

Fernando Barreto, modified 6 Years ago.

RE: Curvilinear Grid - Define spectral files (Answer)

Padawan Posts: 74 Join Date: 6/21/12 Recent Posts
Hi João, you can input the spectrum data to every boundary grid point (a 2D spectrum time series data to every boundary segment). To do this you must write the following keywords in your .mdw file :
[Boundary]
Name = Boundary1
Definition = fromsp2file
OverallSpecfile = Typ1007_Kor.bnd ********(this is the boundary data file)

In your Typ1007_Kor.bnd are present the boundary data (a example file is attached below). This file is iqual the swan output file, where you have for each coordinate (that in your case is the coordinate of the boundary point) the spectrum time series data.
SL
Sha LOU, modified 2 Years ago.

RE: Curvilinear Grid - Define spectral files

Youngling Posts: 6 Join Date: 4/22/14 Recent Posts
Fernando Barreto:
Hi João, you can input the spectrum data to every boundary grid point (a 2D spectrum time series data to every boundary segment). To do this you must write the following keywords in your .mdw file : [Boundary] Name = Boundary1 Definition = fromsp2file OverallSpecfile = Typ1007_Kor.bnd ********(this is the boundary data file) In your Typ1007_Kor.bnd are present the boundary data (a example file is attached below). This file is iqual the swan output file, where you have for each coordinate (that in your case is the coordinate of the boundary point) the spectrum time series data.

Hi, Barreto.

I met the similar questions. I want to setup a combined flow-wave case with the non-stationary 2D spectral wave boundary.

1. According to the WAVE-Manual A2.9, I thought I can directly set the boundary in "boundary conditions-specification of spectral-select from file", insteady of the keywords in .mdw file. Am I right? 

2.In the example of  a 2D stationary Cartesian co-ordinates file (wave-manual page 169), there has two locations in the file.  I know that the co-ordinates of locations in the 2D files are ignored when SWAN reads this. The boundary location is specified in the "define boundary". so are these two locations the boundary start and end location?

3.when I run the flow-wave case, the PRINT file says the following message and the calculation was stopped. do you know why? the boundary location are the same as the flow condition in MDF file with the same grid. I don't think it is outside the grid.

  BOUN SHAPE JONSWAP   3.30 PEAK DSPR POWER
    
  BOUN SEGM IJ         62       321       401       321                  &
 ** Error            : Boundary point outside comp. grid
 ** Error            : Boundary point outside comp. grid
                      CON  FILE 's.bnd'  1
 ** Warning          : No points on the boundaries found
 ** Warning          : At least two points needed for a segment
    
  BOUN SHAPE JONSWAP   3.30 PEAK DSPR POWER
    
  BOUN SEGM IJ        401       321       401         2                  &
 ** Error            : Boundary point outside comp. grid
 ** Error            : Boundary point outside comp. grid
                      CON  FILE 's1.bnd'  1
 ** Warning          : No points on the boundaries found
 ** Warning          : At least two points needed for a segment
    
  BOUN SHAPE JONSWAP   3.30 PEAK DSPR POWER
    
  BOUN SEGM IJ        401         2        61         2                  &
 ** Error            : Boundary point outside comp. grid
                      CON  FILE 's2.bnd'  1
 ** Warning          : No points on the boundaries found