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

Applying new license file on Windows 10

Bilal Ahmed, modified 4 Years ago.

Applying new license file on Windows 10

Youngling Posts: 7 Join Date: 2/27/15 Recent Posts
I am using Delft3D 4.01.01.rc.03 on Windows 10 (64 bit). My license will expire at the end of July 2016. So I requested a new license file from Deltras. But after having the new file, I am getting problems when I want to apply this new license file.

Currently, I have Deltras License Manager (DS Flex) version I compiled the code and installed everything almost one year ago, it was Windows 7 which is recently updated to Windows 10.

Now when I run DS Flex, it shows a warning that “
This version of Windows (Windows 10) is not yet supported ….
”. I ignored the message and chose to continue but eventually it does not apply the latest license file.
Then I tried to use latest version of DS Flex (downloaded through FTP client), which is of version
However at very beginning of installation it shows the message “
The installed version of the Software license manager is too old to be replaced automatically by the Deltras License Manager
Please uninstall version first and then install this version.

Now when I try to uninstall through control panel “Programs and Features”, I am unable to install it; it shows a message “Could not open INSTALL.LOG”.
Then I tried to uninstall by clicking on “UNWISE32.EXE” (from “C:\Program Files (x86)\DS_Flex”) it is apparently uninstalled. But I cannot still install the new version of DS Flex, as it again shows the same message that “The installed version of the Software license manager is too old…”.

I will highly appreciate any help or suggestion.

Adri Mourits, modified 4 Years ago.

RE: Applying new license file on Windows 10 (Answer)

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

To unsinstall the old DS_Flex on Windows10, some manual actions are needed:
On 64-Bits windows:
1. Remove directory: C:\Program Files (x86)\DS_Flex
2. Remove from Registry: HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\WL | Delft Hydraulics\DS_Flex

Then all is clean and you can install the latest DS_Flex.