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! 


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: 

Post your questions, issues, suggestions, difficulties related to our Delft3D Flexible Mesh Suite on the new forum.





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


Message Boards

"Pollutants and tracers" and NEFIS

Hemerson Tonin, modified 8 Years ago.

"Pollutants and tracers" and NEFIS

Youngling Posts: 12 Join Date: 3/29/11 Recent Posts

I'm running a z-layer simulation with some tracers; when I check the results through on Quickplot everything is fine.

However, I need to have the results on NetCDF format. My matlab tools for conversion is working fine for all variables except for the tracers.

Despite some effort I was not able to figure out the name as "pollutants and tracers" are recorded under NEFIS structure which allows me to make some adjustments on the matlab code itself (vs_trim2nc.m).

Suppose my tracer is named as "passive_01" on mdf file. I changed the matlab code and after the conversion I got the "passive_01" variable on the NetCDF file (as result of conversion), however, it doesn't hold any sort of info. I tried some variation (names on code) and the result on the NetCDF file still the same.

Any clue will be welcome.

Adri Mourits, modified 8 Years ago.

RE: "Pollutants and tracers" and NEFIS (Answer)

Yoda Posts: 1221 Join Date: 1/3/11 Recent Posts
Hi Hemerson,

You can start a "nefis file viewer" via "Delft3D-menu", "Utilities", "VSI".
Group "map-const" contains parameter "NAMCON", containing the names of all constituents in a fixed order (only if present):
  • Salinity
  • Temperature
  • Suspended sediments
  • Conservative constituents
  • Secondary flow intensity

Your "passive_01" will be contained in this list, say as constituent number 4 (as an example).
Group "map-series" contains parameter "R1", a 4 dimensional array containing the "concentration" of all constituents in the N,M,K points. The constituent is the fourth dimension. When "passive_01" is the fourth constituent, R1(N,M,K,4) will contain the related concentrations.


Renan Ribeiro, modified 8 Years ago.

RE: "Pollutants and tracers" and NEFIS

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

It's also possible to use the OpenEarth routines in matlab.

vs_use.m - to read the nefis file
vs_let.m - to get the results

and after the routines to create the netcdf file and append the variables


Hemerson Tonin, modified 8 Years ago.

RE: "Pollutants and tracers" and NEFIS

Youngling Posts: 12 Join Date: 3/29/11 Recent Posts
Thanks guys,
it's solved!