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

Error running morphodynamic simulation on Linux

Jacob A Morgan, modified 2 Years ago.

Error running morphodynamic simulation on Linux

Youngling Posts: 4 Join Date: 4/27/18 Recent Posts

We are trying to run a morphodynamic river simulation on a Linux server, however there is a consistent error in the initialization.

*** ERROR Unknown boundary "boundary" in morphology.mor
*** ERROR Flow exited abnormally 

where "boundary" is the name of our upstream boundary and morphology.mor is our morphology characteristics file.


We have isolated the problem to the Boundary block in the .mor file, where we specify IBedCond = 3 and ICmpCond = 1.

   Name             = #boundary#                    Name of boundary as specified in BND file (1 string)
   IBedCond         = 3                             Bedload or bed level boundary condition (1 integer in the range 0 to 5)
   ICmpCond         = 1                             Bed composition boundary condition (1 integer in the range 0 to 3)

Without this block the simulation begins and runs with no problems. However, when the Boundary block is included we get the error message above. The simulation with the Boundary block runs with no problems on a Windows machine. It is only when the Boundary block is included on a Linux machine that it runs into the error.


The Delft3D version on our Linux machine is:

Repository Root:
Repository UUID: 06f92af0-93f6-47d3-9398-6fc6b9b28e5e
Revision: 59590
Node Kind: directory
Schedule: normal
Last Changed Author: zeekant
Last Changed Rev: 59590
Last Changed Date: 2018-07-16 07:11:25 -0700 (Mon, 16 Jul 2018)

And is compiled with IFORT parallel_studio_xe_2017_update3 and using MPICH 3.2.


On our Windows machine the version is:, and is compiled using Visual Studio 2015 with Intel Visual Fortran Compiler Professional Edition 11.1.


Has anyone else encountered this or a similar error? Or does anyone know what a possible solution might be?