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

Delft3D WAVE with 2D Spectra boundary forcing commands

Robert Jenkins, modified 4 Years ago.

Delft3D WAVE with 2D Spectra boundary forcing commands

Youngling Posts: 11 Join Date: 7/28/15 Recent Posts
Hi all,

I've been attempting to run a coupled flow-wave case using 2D spectra from a coarse WAVE run to force the boundaries.
My boundary input is structured correctly as far as I can tell, but I don't believe they are applied correctly as I get bad results.
(Some details on the bad results here: )

In the *.MDW file I use the command...

Definition = fromsp2file
OverallSpecfile = waves.bnd

Which leads to the following command being set in the SWAN input...

BOUN NEST 'wavesxm04.bnd' CLOSED

Is there any flag which can be set in either the MDW or MDF files which will allow me to change the "CLOSED" part of this command to "OPEN?"