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

Longshore currents - LSTF case study

João Gil, modified 8 Years ago.

Longshore currents - LSTF case study

Padawan Posts: 29 Join Date: 10/24/12 Recent Posts
Good afternoon,

I’m currently working on a project which main goal is the simulation of wave-induced longshore currents using the Delft-3D software and its comparison with laboratorial data from LSTF (Visckburg, USA, US Army Engineer Research and Development Center’s Coastal and Hydraulics Laboratory). The experiment intends to represent an infinitely long beach with invariant depth in alongshore direction. For that, the experimental layout uses a recirculation system which is responsible for the uniformity of the longshore currents pattern – see attachment.

Firstly, I would like to know which type of lateral boundaries – LB1 and LB2 in the attachment – you would suggest me to use. I have firstly thought about a kind of “periodic” lateral boundaries. Starting with zero values for the current, they should iteratively be redefined with the calculated values of the longshore current at CS1 in the previous iteration – see attachment. I am hoping this should be a way to represent the uniformity of the flow in longshore direction. The iterations will continue till a stationary condition is achieved. Is there any chance of simulating the problem on this way? If no, which one would you recommend? Would the use of a larger grid for the wave module, in comparison to the grid for the flow module, be a better solution ?

Finally, I would appreciate if you could tell me what type of data I need to input in Neumann boundaries using “time-series” forcing. I have already been looking on the flow manual. Unfortunately I have reached no conclusion.

Thanks in advance,
João Gil
Adri Mourits, modified 8 Years ago.

RE: Longshore currents - LSTF case study

Yoda Posts: 1221 Join Date: 1/3/11 Recent Posts
This thread is continued here.