intro story Coast / Estuary

Coast / Estuary

Coastal systems are among the most dynamic physical systems on earth and are subject to a large variety of forces. The morphodynamic changes occurring to coastlines worldwide are of great interest and importance. These changes occur as a result of the erosion of sediments, its subsequent transport as bed load or suspended load, and eventual deposition. 
Estuaries are partly enclosed water bodies that have an open connection to the coast. Estuaries generally have one or more branching channels, intertidal mudflats and/or salt marshes. Intertidal areas are of high ecological importance and trap sediments (sands, silts, clays and organic matter).
Within the Delft3D modelling package a large variation of coastal and estuarine physical and chemical processes can be simulated. These include waves, tidal propagation, wind- or wave-induced water level setup, flow induced by salinity or temperature gradients, sand and mud transport, water quality and changing bathymetry (morphology). Delft3D can also be used operationally e.g. storm, surge and algal bloom forecasting. 
On this discussion page you can post questions, research discussions or just share your experience about modelling coastal and/or estuarine systems with Delft3D FM. 




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



Message Boards

ERROR d50 < 0.0001 not allowed

Arjan Mol, modified 5 Years ago.

ERROR d50 < 0.0001 not allowed

Youngling Posts: 1 Join Date: 11/17/11 Recent Posts

I am doing a Delft3D coupled flow-wave simulation (version Version, with a non-cohesive sediment fraction with a D50 of 90 micron. Although the user manual says (Section that the lower limit of the D50 is 64 micron, my simulation does not start and comes with the message: "*** ERROR d50 < 0.0001 not allowed".

BTW, I have noticed that when I do a FLOW-only simulation (without coupling with WAVE), this error does not pop up.

Arjan Mol
Germán Aragón, modified 5 Years ago.

RE: ERROR d50 < 0.0001 not allowed

Youngling Posts: 10 Join Date: 6/18/13 Recent Posts

Same error with 64 micron NON-COHESIVE, with Delft3D-WAVE Version and FLOW2D3D Version transport formulation van Rijn 1993

In only Flow simulation works correctly too. Some help, please...

Qinghua Ye, modified 5 Years ago.

RE: ERROR d50 < 0.0001 not allowed (Answer)

Jedi Council Member Posts: 612 Join Date: 3/2/11 Recent Posts
Hi Arjan and Germán,

Yes. Indeed it is not allow to use a sediment fraction d50 less than 0.0001 with wave using default Van Rijn 1993. If not with wave, it works fine. This is deliberately set in the code. You have to use VR2004 or later. In VR2004, the d50 cannot be smaller than 8.0e-6 as well.

These are threshold given by Van Rijn. Does this help a bit?


Germán Aragón, modified 5 Years ago.

RE: ERROR d50 < 0.0001 not allowed

Youngling Posts: 10 Join Date: 6/18/13 Recent Posts
It does for sure!

Aspen M Anderson, modified 7 Months ago.

RE: ERROR d50 < 0.0001 not allowed

Youngling Posts: 3 Join Date: 8/5/18 Recent Posts

I am pretty new to Delft3D so this may be a silly question, but is there as easy way to change the VR1993 transport equation to the VR2004 equation?

Thanks, Aspen


Update: I found a solution here