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

Switching between SP/DP computation

Tobias Rothhardt, modified 9 Years ago.

Switching between SP/DP computation

Youngling Posts: 17 Join Date: 7/25/11 Recent Posts
Hi there,
I try to switch to SP computation but while checking the tri-diag file it still uses DP. I used the changeprecision.tcl script, recompiled delft and have the besides the standard I changed the ini file to the _sp but it changes nothing.

Did I miss something ?

Adri Mourits, modified 9 Years ago.

RE: Switching between SP/DP computation (Answer)

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

No, that looks fine.
Do you use the GUI or plain scripts? Try using scripts.
In the diag-file is also echoed the build date and time. Does that match your newly created SP version? In that case your SP version is not Single precision. Otherwise you use another executable by accident.