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Hi.

I'm working with a 3D-model in which I have two river and one open boundaries. I have this model working for 2012 with tides, realistic river discharge and wind forcing.
Now, I am trying to model 2015 with the corresponding river discharge for this year. To be sure that everything is working, I'm trying only with tides and river discharge. But the model keep failing despite the only difference between this model and the previous one is the river discharge file and the initial date of the model.
At first, I thought that the problem was in the format of the river discharge file but the output log indicate the correct values of liquid boundary. Nonetheless, I tried to format the river discharge file with tabs, and then with spaces but nothing works.

The output file says thatbut the values of the river discharge are similar (even lower) than 2012 so I don't think that I should modify the maximum iterations or the precision of the model. What else could be causing the problem?

I have attached the steering file, the river discharge file and a log of the model.

Thanks in advance.

Hello Crojas,

Please change the extension of you .log file to .txt so that it can be read by other users (some extensions are not allowed by this website).

Anyway, my first idea is that you should change your initial condition, in particular INITIAL ELEVATION. If you change the date, you would be very lucky if the same initial elevation also works.

Hope this helps,

Chi-Tuan

Hi,

Thanks for your answer. I've attached the log file with a txt extension so it can be read without problems.

I'll try changing the INITIAL ELEVATION and I'll let you know if it works.

Thanks.

Hello again,

I've tried to run the model with a initial elevation of 1.5 (before I tried with 3.5) but I got the same error as before:
So that didn't work. If I understand the log correctly, the model does not run not even for one time step. Do you have any other idea what could be the problem? Or if there is any way to debug this?

Thanks

Do you use any initial conditions file?

From what I see you cold start the model and your boundary condition does not meet initial condition.

Hope that helps,
Patrick

Hello,

How did you determine your initial elevation?
With your previous computation in 2012, did it start on January 1st?
What is the reference level of the bottom elevation? Chart Datum, Mean Sea Level? Something else?

Personnaly, I would try the prediction of tide level on January 1st 2015 at 0:00 UTC if using Chart Datum for initial elevation (translated if another reference level).

SHOM webiste seems to predict a tida level = 4.3 m CD.

Anyway, if you got NaN, you can try to decrease the time step.

If these 2 ideas are not enough, as told in other posts, when getting NaN in your listing (Not a Number), you should use a debug configuration with debug options to investigate.
See e.g. the S9.gfortran.debug configuration in the $HOMETEL/configs/systel.edf.cfg configuration file, in particular the flag fflags_debug_gfo for gfortran compiler.
fflags_debug_gfo: -g -Wall -fcheck=all -fbacktrace -fbounds-check -finit-integer=-1 -finit-real=nan -ffpe-trap=invalid,zero,overflow

It will show in which subroutine the issue/nan occurs and may help you to change something in your computation.

Hope this helps,

CHi-Tuan

PMV wrote:
I'm not using a initial conditions file.

pham wrote:
I'm just starting to learn how to model so I didn't pay too much attention to the initial elevation value, I'll check a better value for this. About the starting date, in both models is January 1st (2012 and 2015). I've tried increasing and decreasing the time step and neither of these options work. I ended up diminishing the accuracy of the model and increasing the iterations and now the model is working but I still don't know where the problem was.

I'll try now to use the debug configuration as you suggested to know where the problem occurs.

Thank you both for your help.