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

Model calibration

Reda Bernotaite, modified 7 Years ago.

Model calibration

Youngling Posts: 1 Join Date: 5/28/13 Recent Posts
Dear Delft3D users,

I really need some help.

I am trying to calibrate my lagoon model according to example of a model I have (model was made with Mike21). But I certainly somewhere do mistakes, cause it doesn‘t work as should.

The only calibration constituents are wind 0-9 m/s SE (135 deg) and water debit 1220 m3/s (water level is 0). Normal roughness in lagoon is 33 (manning), but the one counted by Mike21 is 0.032. Water speed, what I should get is 0,35 m/s.

I take Total discharge Time-series south boundary and Water level Time-series north boundary and 60 m time step (water should go from south to north).

But I always get „Water level too high > 25.00 m ..„ error after 4th timestep. What am I doing wrong?

I attach my .rgd, bathymetry and .mdf files and expect for some kind help.



Maarten van Ormondt, modified 7 Years ago.

RE: Model calibration

Padawan Posts: 45 Join Date: 3/11/11 Recent Posts
Hi Reda,

I think your model time step should be in the order of 0.5 minutes (or perhaps even less). 60 minutes is way too high. Please check the Delft3D manual on time steps and the Courant criterion.

Maarten van Ormondt
Phil Shepperd, modified 7 Years ago.

RE: Model calibration

Padawan Posts: 33 Join Date: 5/31/11 Recent Posts
Hello. Manning should be specified as 0.033, rather than 33 ............ this is quite a high value by the way, try values around 0.022.

Apart from that, and the timestep as already pointed out, it should be fine. Good luck.