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 FM- Waves errors

Christopher Mahlathi, modified 2 Years ago.

Delft3D FM- Waves errors

Youngling Posts: 4 Join Date: 10/25/17 Recent Posts
Good day

Does anyone know what his error means;

Execution of Waves has failed.
External component has thrown an exception.

I get this every time I try to run D-waves simulations

Emiel Moerman, modified 2 Years ago.

RE: Delft3D FM- Waves errors (Answer)

Padawan Posts: 84 Join Date: 3/10/11 Recent Posts
Hi Chris,

I have answered your question through the official Delft3D support line. But here a short answer as well for the community.
Basically there is not just one answer to the error statement you are getting. It basically just means that something is wrong in your input.
In you case it was a combination of things:

- there were double output locations in the *.loc file
- wind growth and quadruplets were activated but the wind speed was set to 0
- the OnlyVerifyInput was set to true (not completely sure if this actually matters/causes the problem)

Changing these settings solved the error.

A good approach to solve an issues which doesn't directly tell you what is wrong in detail is always to simplify the model and built it back up step by step to isolate were the issue is coming from.
And then solve it there.


Christopher Mahlathi, modified 2 Years ago.

RE: Delft3D FM- Waves errors

Youngling Posts: 4 Join Date: 10/25/17 Recent Posts
Thank you Emiel,

I have not yet received feedback from the official channels yet, I'm not sure if it is a fire wall issue in our company.

However, after following your above suggestions I was able to resolve all my issues. Thanks again.