2.2.2 Inland water simulations

Small closed system simulation

2023-04-14T10:14:23Z

Hi, I would like to know if it is possible to use DELFT 3D to model a small circular tank (1.1M3) forced only by meteorological conditions (no inflows or outflows). I've tried to set up this system but the model seems to be unstable and when I add wind data it crashes with the following error: *** ERROR NaN found after 3130 timestep(s). ps. I already tried decreasing the timestep and still not working

error of model validation report

2023-03-12T11:59:52Z

When I rune a model. In the model validation Report, Miscellaneous remind me a error: Parameter Start time Outside Validity range[0,+inf].
I really you give me a hand!

No convergence in DIFU

2022-11-23T12:20:21Z

Hello, good morning. I am working on a model of a coastal wetland with numerous tributaries. The outflow from the lake to the sea is controlled by gates. The inflows I have introduced in the model as discharges while the outflows as open boundary. Both inlets and outlets are known. When I run the model I get warnings about the Courant number, which is slightly greater than 1.

However, now I want to study the distribution of a pollutant in the lake. When I enter the loads I get many warnings; the most worrying one is "No convergence in DIFU for resp. constituent nr. & tstep: 1 8088" and the concentrations become negative from then on. I don't quite understand where the problem lies, as the model reflects the hydrology of the lake very well.
I am attaching all the inputs to my model in a zip file if anyone would like to take a look at it. Any suggestions are appreciated.

Initial condition file and Z-model

2022-01-21T09:16:49Z

Hi!

In the Delft3D-Flow manual it is stated that the initial condition file is not yet available for the Z-model. Is this still true? What is then the correct way to create vertical-variable initial conditions in the Z-model?

Any help would be appreciated!

Thanks in advance,
Emma

Heat flux model and WARNING negative concentration for l, k, nst:

2021-09-30T12:07:39Z

Hello!

I am writing to ask about a warning that appears in my simulations and to tell you about my research on the subject. I am using Delft3D version 4.04.01.

First, my model represents an estuary, under temperature and salinity processes and which is forced with astronomical tide at sea and with freshwater discharges in several upstream areas. The heat flux models used are absolute flux, net solar radiation and absolute flux, total solar radiation. The model is divided into 12 domains and is executed using DomainDecomposition. Warning messages appear when turning on the heat flux models and appear both when launching the complete simulation and when launching individual domains.

The Warnings are as shown in the attached image. In them we have a position, l, which does not refer to the mesh location, and a position, k, which refers to the layer. Sometimes they appear only in the first layers (k=1,2); however, it is common for them to appear in all of the layers and to appear duplicated, as shown in the attached image. I have not found any pattern associated with sea level change.

Regarding the heat flux model used, I have found that as the radiation value increases, the warnings decrease and that using the total solar radiation model, they decrease significantly and even disappear depending on the domain. In particular, I have found that the warning appears more frequently in smaller domains, which have more meanders.

The warning does not seem to affect the results, but it generates a lot of noise in the -tri.diag files, which prevents other warnings or errors from being seen.
Does anyone know more about this warning, why does it appear, what cells and constituents does it refer to?

Thank you very much in advance,

Best regards,

Pablo