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

Nearshore water level modelling is not accuracy

Bing Zhao, modified 4 Years ago.

Nearshore water level modelling is not accuracy

Youngling Posts: 13 Join Date: 5/31/16 Recent Posts
Hi there,

Recently I modelled tide flow with DelftDahsboard and Delft3D. I make the open boudaries with Astronomic type which is generated by DelftDahsboard. I can get accuracy water level in the deep sea. But the nearshore water level is very bad compared with the tide station. It seems the shape is the same between the modelling and the tide station's water level, but the modelling water level is about 2 days later than the tide station's water level. Why? Please help me! I will attach the water level pictures. The black line is the tide station's water level, and the blue line is the modelling result.

Best regards,
Qinghua Ye, modified 4 Years ago.

RE: Nearshore water level modelling is not accuracy

Jedi Council Member Posts: 610 Join Date: 3/2/11 Recent Posts
Hi Zhao Bing,

I don't know if it is still a problem for you. But this is normal, for the offshore, the tidal long wave is less influenced by the nearshore processes. In the nearshore, the bed friction, wave-wave interaction, land scape all will change the wave shape of the tidal signal. This is all it is about, that we need models to reproduce this transformation.

Thus this is why you need Delft3D-like tools to do the study. Just for your information, Deltares also offeres individual service for model setup, model review etc. If you really need, pls contact them.