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. 
 

** PLEASE TAG YOUR POST! **

 

 

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

 

 

Message Boards

RE: NaN after 2 timesteps using tag 3426

DK
Dmitry Kushnir, modified 5 Years ago.

NaN after 2 timesteps using tag 3426

Padawan Posts: 85 Join Date: 11/9/12 Recent Posts
Hi all,

Recently I tried to run the Z-layered model using tagged version 3426. The tri-diag file showed that it had crashed due to NaNs.


********************************************************************************
***
*** Deltares, FLOW2D3D Version 6.01.06.000000, Feb 22 2014, 13:55:32
*** built from : https://svn.oss.deltares.nl/repos/delft3d/tags/3426
***
*** runid : Z_2012
*** date,time : 2014-02-22, 14:19:39
***
********************************************************************************

*** MESSAGE Executable for 32-bits platform.
*** MESSAGE Double precision computation using reals of kind 8
*** MESSAGE Z-model used
*** MESSAGE Local time zone is UTC + 2.0 hours
*** MESSAGE Ocean heat model: Stanton number specified to be 0.13000E-02
*** MESSAGE Ocean heat model: Dalton number specified to be 0.13000E-02
*** MESSAGE Using precipitation/evaporation specified in file Prec_eva.eva
*** MESSAGE Evaporative heat flux is calculated internally, independent of the prescribed mass flux
*** MESSAGE Using UNESCO density formulation by default
*** MESSAGE Number of pivot points to convert wind speed to wind drag coef.: 3
*** MESSAGE Momentum solver mdue method is specified
*** MESSAGE DRYFLP and DPSOPT both specified in MD-file. Using DPSOPT: DP
*** MESSAGE Transport solver van leer-2 method is specified
*** MESSAGE Uniform wind and pressure specified
*** MESSAGE Heat model: Secchi depth specified to be 1.5000000 m
*** WARNING Combination of Z-model and Evaporation model has not yet been tested
*** MESSAGE 45 deg. Staircase Boundary read
*** ERROR NaN found after 2 timestep(s).
*** ERROR Flow exited abnormally


Reducing the timestep yielded no results. I've newer encountered such a problem with previous version 3185. And I've also noticed that sigma-layered models run well with 3426 but crashes after switching to Z-layers.

Any input is greatly appreciated.

Regards,

Dmitry
Qinghua Ye, modified 5 Years ago.

RE: NaN after 2 timesteps using tag 3426

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

Thanks for your message!

Can you share your input with us to better target the problem? (Through dropbox or should I send a email to you?) The tagged version passed our test benches. I would not expect this would happen.

Regards,

Qinghua
DK
Dmitry Kushnir, modified 5 Years ago.

RE: NaN after 2 timesteps using tag 3426

Padawan Posts: 85 Join Date: 11/9/12 Recent Posts
Hi Qinghua,

Many thanks for your prompt response. It would be great if you sent me an e-mail to kushnir.dmitry23@gmail.com. I would be able to send input files to you after a couple of hours.

Regards,

Dmitry
Qinghua Ye, modified 5 Years ago.

RE: NaN after 2 timesteps using tag 3426 (Answer)

Jedi Council Member Posts: 612 Join Date: 3/2/11 Recent Posts
dear Dmitry,

The same as the mail I sent you, Indeed there was a problem in the tagged version 3426 for z-layer models, which is resolved in the version come afterwards revision 3456. The problem was the initialization of dry cells and dry edges and caused NaN’s there. In rev. 3456, this problem has been solved.

Thanks,

Qinghua