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

problem with river sediment simulation

Mathilde Henri, modified 5 Years ago.

problem with river sediment simulation

Youngling Posts: 1 Join Date: 5/17/15 Recent Posts
Hello everyone,

I'm using Delft3d for my dissertation. I'm trying to model the hydrodynamics and morphological changes due to a turbine in a river near a meander.
It works for the hydrodynamic part but I have troubles with the sediment simulations. It looks like the sediments increase up to 10^38 after a few time steps and then completely disappear after another few time steps.
Also, the simulation crashes if I put the 'spin-up interval before morphological changes' before the sediments disappear because of a water level error but it runs to 100% otherwise.

I've been struggling with this problem for a few weeks now and have tried a lot of things but never managed to get the sediments to appear til the end of the simulation time.

Has anyone had a similar problem or would anyone have an idea about what creates that problem?

Thank you very much.