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

Tidal forces implementaions

Diego Uribe Suárez, modified 6 Years ago.

Tidal forces implementaions

Youngling Posts: 2 Join Date: 12/12/13 Recent Posts
I am working on Caribbean Sea model, and I am trying to implement the tidal forces option, but when I compare the results with tide measurements in the area, the spring and neap periods do not match with the results of the model. Any idea how can I fix it??
Anas Rahman, modified 6 Years ago.

RE: Tidal forces implementaions

Youngling Posts: 21 Join Date: 10/4/13 Recent Posts
Hi Suarez,

Have you checked the open boundaries for your model?

It is recommended NOT to use the same type of boundary conditions for all open boundaries.

As for me, it works using a combination of Water Level and Current.

Hope this helps

Giordano Lipari, modified 6 Years ago.

RE: Tidal forces implementaions

Youngling Posts: 12 Join Date: 3/23/11 Recent Posts
Hi Diego

I realise you may have fixed your issue for a long time. I bumped into your request for help right now.

If not yet, my question is whether the problem only regards the time shift or the amplitudes as well. Could you attach a plot comparing the computed and reference water elevation? Ideally they could be two: one for one spring-neap cycle and one for a narrower window of 2-3 days where you see the largest differences.

Based on this evidence we can speculate something on whether this comes from parameter/files settings or from some other more fundamental choices.

Hope this helps