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! 

 

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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: 
/web/delft3dfm/forum

Post your questions, issues, suggestions, difficulties related to our Delft3D Flexible Mesh Suite on the new forum.

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** PLEASE TAG YOUR POST! **

 

 

Sub groups
D-Flow Flexible Mesh
DELWAQ
Cohesive sediments & muddy systems

 


Message Boards

Problem to restart with a finer grid

GD
Gonzalo Duro, modified 6 Years ago.

Problem to restart with a finer grid

Youngling Posts: 11 Join Date: 12/4/13 Recent Posts
Hello,

I am having troubles to make a restart simulation from a coarse mesh to a finer one. I manually did with QUICKIN the interpolation for some bed level points (*.dep file) that were not picked up by the interpolation technique so not to have NaN points, but still when I try to perform the restart, the simulation crashes before any computation.

Maybe there is a limit in the refinement step which I am not respecting, e.g. not to jump from a 4 meters cell to a 1m cell, which is actually my case.

Is there a way out to perform restarts with substantial grid refinements?

This is the message of one of the attempts:
[indent]
--------------------------------------------------------------------------------
Deltares, Delft3D-FLOW Version 4.00.01.000000, Mar 15 2011, 10:57:16
flow2d3d.dll entry RUNME
--------------------------------------------------------------------------------

Part I - Initialisation Time Dep. Data module...
runid : S2_14_1cm
Part II - Creating intermediate files...
Part III - Initialisation of the Execution module...

------------------------------------------------------------------------------
FINISHED Delft3D-FLOW
runid : S2_14_1cm
date, time : 2013-12-31, 01:06:35
*** ERROR No Fmtbnd record in MD-file, item will be skipped ?!
*** ERROR Fmtbnd - insufficient number of values or record is corrupt
*** ERROR No FmtbcH record in MD-file, item will be skipped ?!
*** ERROR FmtbcH - insufficient number of values or record is corrupt
*** ERROR No Fmtsta record in MD-file, item will be skipped ?!
*** ERROR Fmtsta - insufficient number of values or record is corrupt
*** ERROR No Fmtbnd record in MD-file, item will be skipped ?!
*** ERROR No FmtbcH record in MD-file, item will be skipped ?!
8 errors and 0 warnings
returning to main program from domain S2_14_1cm
------------------------------------------------------------------------------[/indent]

Thanks in advance!

Gonzalo
Qinghua Ye, modified 6 Years ago.

RE: Problem to restart with a finer grid

Jedi Council Member Posts: 612 Join Date: 3/2/11 Recent Posts
Hi Gonzalo ,

Can you also provide the tri-diag file as well?

The problem you described is not very clear. You want to have a restart file for a finer grid, but you manually interpolated the bathymetry file. What is the point?

The refinement in Delft3D grid doesn't have limitation.

Regards,

Qinghua
GD
Gonzalo Duro, modified 6 Years ago.

RE: Problem to restart with a finer grid

Youngling Posts: 11 Join Date: 12/4/13 Recent Posts
Hello Qinghua, thank you for your reply.

I attach the tri-diag file.

The problem I face is when I try to simulate with the initial conditions of a previous simulation that had a coarse grid. As far as I know, for the initialization of the run two type of data are needed: hydrodynamic and morphodynamic.

Well, the first error I encountered was related to the lack of bed level points in the bathymetry. I generated a sample file from the 'coarse' run with the QUICKPLOT program. When I inserted the sample points in QUICKIN to do the triangular interpolation into the finer grid, many points were not 'filled' (mainly in the boundaries) so I had to manually add the missing points to have a complete bathymetry for the new ('finer') run. So, I believe this procedure solved the problem related to the NaN points in the bathymetry.

After that, a second problem arrived. I guess this time is related to the hydrodynamic data, that has to be read from the .map file. I suspect that the software is unable to interpolate from the coarse grid to the finer grid the values of the velocities, water levels, and so, especially in the boundaries (as I experienced with the bathymetry).

So my questions are:
1) Is the problem correctly interpreted and presented?
2) Is there a way to make the simulation run despite the difference in the grid size between both simulations?
3) Is there an easier way to make the restart from coarse to fine grids without having to manually add the missing data points?

Please do not hesitate to ask for further explanations if I did not clearly presented the problem.

Thank you very much for your time

Gonzalo
Adri Mourits, modified 6 Years ago.

RE: Problem to restart with a finer grid

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

Can Delft3D-NestHD help you? See the manual, chapter F.

Regards,

Adri
GD
Gonzalo Duro, modified 6 Years ago.

RE: Problem to restart with a finer grid

Youngling Posts: 11 Join Date: 12/4/13 Recent Posts
Dear Adri,

Thank you for your reply.

I think that another possible solution for the problem is to build an Initial Conditions File <name.ini> as indicated in Chapter A.3.9 of the Manual. Unfortunately, this procedure implies a manual interpolation of all the variables into the new grid, but it is still a way out.

Best regards,

Gonzalo