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

Tangential boundary conditons

Fernando Barreto, modified 7 Years ago.

Tangential boundary conditons

Padawan Posts: 74 Join Date: 6/21/12 Recent Posts
Anyone have any information regarding the implementation of the tangenctial boundary condition on Delft3D. I've read the document ''Implementation and validation of tangential boundary conditions in Delft3D'' and generated Riemann and tangential boundary conditions with nesthd2, but the manual says that Delft3D does not accept this type of boundary.


Adri Mourits, modified 7 Years ago.

RE: Tangential boundary conditons (Answer)

Yoda Posts: 1221 Join Date: 1/3/11 Recent Posts
Hi Fernando,

This development is in a research branch. Merging this in the trunk is on our TO DO list. But it is not clear when this will happen; it is not planned yet.

You are free to use this branch yourself, but be aware of the following restrictions:
  • Branch versions are not fully tested.
  • Branch versions may lack behind compared to the trunk with respect to bug fixes.
  • Using a branch version is your own responsibility.
  • Support by Deltares can not be guaranteed.