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

Roller model

karunakar kintada, modified 5 Years ago.

Roller model

Padawan Posts: 35 Join Date: 7/31/12 Recent Posts
Hi all,
As you all know, the roller model in Delft3D is quite impressive. But i'm curious to know if i can turn off the same in one domain of a Domain decomposition model.
So that it is active in my area of interest.
Some of you may ask why, the reason is it at time creates an instability in coarse mesh domain.

All suggestions are welcome.
Thanks in advance.
Adri Mourits, modified 5 Years ago.

RE: Roller model (Answer)

Yoda Posts: 1224 Join Date: 1/3/11 Recent Posts
Hi Karunakar,

I did not try it myself, but expect that it should work: you don't need to specify space varying roller input, it's just a process being switched on.

But the roller data that enters your subdomain of interest via the DomainDecomposition-boundaries will be zero. This will lead to a neglected factor. This factor will be small when the DD-boundaries are "far away" and preferably in "deeper water".

Please report your findings here on the forum.



karunakar kintada, modified 5 Years ago.

RE: Roller model

Padawan Posts: 35 Join Date: 7/31/12 Recent Posts
Thanks adri,
i'm working on it. I'll certainly post once i'm sure about other physics involved.
Thanks a lot.