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

Nudging in Delft3D

Fernando Barreto, modified 4 Years ago.

Nudging in Delft3D

Padawan Posts: 74 Join Date: 6/21/12 Recent Posts
Hi all,

I'd like to know how nudging, activated by the flag ''Nudge=# Y # ", works in Delft3D; in which variables is nudging applied? Is there a way to change nudging parameters?

Thanks in Advance
Adri Mourits, modified 4 Years ago.

RE: Nudging in Delft3D (Answer)

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

When nudging is switched on, it is only applied on the constituents (temperature, salinity, tracers, sediments) at open boundaries. You can only change the related parameters in the source code.

It's introduced by a colleague. I'll ask him to add more info here.


Fernando Barreto, modified 4 Years ago.

RE: Nudging in Delft3D

Padawan Posts: 74 Join Date: 6/21/12 Recent Posts
Thanks a lot Adri,

I'd appreciate a lot more information about this topic.


Fernando T C Barreto