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

Issue with Flow-Wave online coupling

Maumoon Saleem, modified 3 Years ago.

Issue with Flow-Wave online coupling

Youngling Posts: 2 Join Date: 7/5/16 Recent Posts

I am having some issues with running my Flow with Wave in online coupling. When I start a run, everything initializes well and the swan completes a run. But the problem comes with the subsequent Flow calculation which uses the com file from Wave. I am getting an error that says:

"NEFIS message 9002:
Element "DISS " of group "WAVTIM " not found on file "com-run_2.dat"

And the process halts. I am experiencing this same issue with some of the provided tuturial examples for coupling too.

Following are my Wave and Flow versions:

Delft3D-WAVE Version
Delft3D-FLOW Version

I have run my model separately on both Flow and Wave, they run perfectly. The issue comes up during coupling. I would be grateful if I could be pointed in the right direction in order to correct this error.

Qinghua Ye, modified 3 Years ago.

RE: Issue with Flow-Wave online coupling

Jedi Council Member Posts: 612 Join Date: 3/2/11 Recent Posts
hi Maumoon,

It seems to me that the problem comes from different version of wave and flow binaries. Can you try to use the same installed version of wave and flow?