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

Modifying the source code to adapt the date as a julian day

Rodrigo Carballo, modified 5 Years ago.

Modifying the source code to adapt the date as a julian day

Youngling Posts: 19 Join Date: 5/27/11 Recent Posts

I am trying to adapt the code to read the initial date as a julian day.

Could anyone tell me where in the source code the tidal harmonics and the simulation initial date are read, as well as these input data are combined to simulate the tidal forcing for the specified date?

Kind Regards
Adri Mourits, modified 5 Years ago.

RE: Modifying the source code to adapt the date as a julian day

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

Tidal harmonics (using astronomic components): ...src\engines_gpl\flow2d3d\packages\io\src\preprocessor\asc.f90
Initial date: ...src\engines_gpl\flow2d3d\packages\io\src\input\rdirt.f90

The following file contains some julian day subroutines: ...src\utils_lgpl\deltares_common\packages\deltares_common\src\time_module.f90