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: 

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D-Flow Flexible Mesh
Cohesive sediments & muddy systems


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Astronomical constituents to use when prescribing water level boundary cond

Rafael Santana, modified 2 Years ago.

Astronomical constituents to use when prescribing water level boundary cond

Youngling Posts: 1 Join Date: 9/29/15 Recent Posts
Hi everyone,

I am trying to include new astronomical constituents in my delft3d .bca file for water level boundary condition. I have a tried a test including new harmonic constituents from a tidal station located inside my domain. The results were worse than the previous run forced with a fewer number of constituents (figure attached).

The new constituents were selected based on its statistical representation and on the list presented in the Table C.1: Astronomical constituents from Delft3D-FLOW_User_Manual. However, the table presents the constituents that can be used when prescribing astronomical boundary conditions for the flow. Please, find bellow the message the list of astronomical constituent used.

Is there a list for astronomical constituents that can used when prescribing astronomical boundary conditions for the water level?

Thanks in advance,

Rafael Santana

List of astronomical constituent used:

19 tidal constituents from original run:

MF 1.7400000e-02 3.4176000e+02
S1 8.4000000e-03 2.6020000e+01
L2 2.5700000e-02 1.8307000e+02
T2 1.7300000e-02 1.9974000e+02
M2 7.4267467e-01 1.7950667e+02
S2 3.0436738e-01 1.9593998e+02
N2 1.4462450e-01 1.7547325e+02
K2 8.2963919e-02 1.9828336e+02
2N2 1.9655112e-02 1.7612636e+02
MU2 2.5597758e-02 1.8978121e+02
NU2 2.0986982e-02 1.8978121e+02
K1 3.7761319e-02 2.4957741e+02
O1 6.1721026e-02 1.5257419e+02
P1 1.3633841e-02 2.3450545e+02
Q1 1.6716639e-02 1.2103438e+02
M3 1.1702674e-02 2.2643899e+02
M4 1.4449487e-02 4.7976428e+01
MS4 1.0432072e-02 1.5490388e+02
MN4 5.5874579e-03 3.2227753e+02

53 tidal constituents from original run:

MF 1.7400000e-02 3.4176000e+02
2Q1 3.0000000e-03 8.3440000e+01
SIG1 2.8000000e-03 1.1155000e+02
Q1 1.6622311e-02 1.2103438e+02
RO1 3.1000000e-03 1.2429000e+02
O1 6.1539028e-02 1.5257419e+02
TAU1 1.0000000e-03 3.0719000e+02
NO1 2.0000000e-03 2.2823000e+02
CHI1 5.0000000e-04 2.0901000e+02
PI1 8.0000000e-04 2.3060000e+02
P1 1.3624051e-02 2.3450545e+02
S1 5.0598802e-03 2.5867345e+01
K1 3.7682186e-02 2.4957741e+02
PHI1 7.0000000e-04 2.8564000e+02
J1 1.5000000e-03 3.3966000e+02
SO1 5.0000000e-04 4.5340000e+01
OO1 2.2000000e-03 6.0520000e+01
OQ2 3.2000000e-03 1.6153000e+02
EPS2 6.9000000e-03 1.8241000e+02
2N2 1.9738922e-02 1.7612636e+02
MU2 2.4615840e-02 1.8978121e+02
N2 1.4347545e-01 1.7547325e+02
NU2 2.4537146e-02 1.7092008e+02
GAM2 2.5000000e-03 1.9860000e+02
M2 7.4059086e-01 1.7950667e+02
MKS2 3.7000000e-03 2.6309000e+02
LDA2 9.3000000e-03 1.3747000e+02
L2 1.5311973e-02 1.8310003e+02
T2 1.7300000e-02 1.9974000e+02
S2 3.0144289e-01 1.9593998e+02
R2 4.8000000e-03 2.2758000e+02
K2 8.2500059e-02 1.9828336e+02
MSN2 5.7000000e-03 3.2715000e+02
ETA2 5.4000000e-03 2.1597000e+02
MO3 4.0000000e-04 3.0332000e+02
M3 1.1505236e-02 2.2643899e+02
SO3 7.0000000e-04 2.3373000e+02
MK3 1.2000000e-03 3.1000000e+02
SK3 5.4000000e-03 6.7000000e+00
MN4 5.6734228e-03 3.2227753e+02
M4 1.4529066e-02 4.7976428e+01
SN4 1.9000000e-03 1.7386000e+02
MS4 1.0472855e-02 1.5490388e+02
MK4 2.3000000e-03 1.5847000e+02
S4 1.1000000e-03 1.6984000e+02
2MK5 6.0000000e-04 2.7872000e+02
2MN6 1.7000000e-03 1.8951000e+02
M6 3.0000000e-03 1.9453000e+02
2MS6 2.7000000e-03 2.0370000e+02
2MK6 7.0000000e-04 2.0879000e+02
2SM6 8.0000000e-04 2.0950000e+02
MSK6 5.0000000e-04 2.2360000e+02
M8 3.0000000e-04 3.0384000e+02