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

Coupling WAVE and FLOW: extend or do not extend?

Paolo Gyssels, modified 4 Years ago.

Coupling WAVE and FLOW: extend or do not extend?

Youngling Posts: 21 Join Date: 4/20/11 Recent Posts
Daer guys

I'm now studying coupling wave and flow (tide+wind actions) models.

Please, may you explain me wht is the difference between the options in Hydrodynamics: a) don't use b) use but don't extend c) use and extend ?

I believe that don't use is that you do not consider any coupling, but I do not understand what is the real difference between b) and c). I'm trying and exploring differences running different test.

Moreover, how can I introduce time varying wave conditions usin the flow coupling? I cannot find any place where I can do that (Time frame options desappear if I use coupling flow+wave)

Thank you very much for any help

Best regards

Paolo Gyssels
Paolo Gyssels, modified 4 Years ago.

RE: Coupling WAVE and FLOW: extend or do not extend?

Youngling Posts: 21 Join Date: 4/20/11 Recent Posts
Dear all

I saw that generating a TPAR file is the best way to incorporate time varying wave boundary conditions. The problem is that the firs time you have to modify manually the .mdw file as written in the manual, then a new botton appears in the GUI.

As regards the use and extend I'm trying... (see manual p.26 at the end) but it is not totally clear to me