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

refine upper layer in z-layer configuration

Diego Pantoja, modified 1 Year ago.

refine upper layer in z-layer configuration

Youngling Posts: 2 Join Date: 6/26/19 Recent Posts

Hi everyone

Currently we are running a hydro-configuration in z-layer, and then we want to use those results to run a Part-configuration.

My question is, Is there any parameter to set the sigma-layer (in delft-part) to reverse (up-down) the current discretization?, 

Obviously we seek for a finer discretization on upper layers, but as you can see in the figure attached, the resolution increases always on bottom layers.

When we start the Part-configuration from a hydro-configuration in sigma-layer everything goes well, but what we want and what we are currently using is a z-layer configuration.

I hope you can help us, 

Thank you,