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Hi everybody.
I am simulating a flooding in an Albanian zone and I'm having some problems with the boundary condition of the upstream. I have an inflow at the inlet that varies in time (open boundary with prescribed flowrate) and the sea at output (open boundary with prescribed elevation). In attached the representetion of my case. I have realized a hotstart that seems to be ok, in fact in its last frame the inlet is wet. But when I launch the unsteady-state simulation (with the hotstart), the program stops after few iterations (maximun 1 minute) giving the following error: DEBIMP : PROBLEM ON BOUNDARY NUMBER 2 (upstream), GIVE A VELOCITY PROFILE IN THE BOUNDARY CONDITIONS FILE OR CHECK THE WATER DEPTHS. I also tried not to use the hotstart, but the same error appears. I really

don't know how to solve my problem, any ideas? Thank you in advance :)
Flavio

Hi
This kind of problem has been mainly discussed on the forum.
If your case starts and stop after few iterations this means the inlet becomes dry. So you could have a problem with the discharge value or a torrential inlet which require also an impose water level.
Have a look on the forum to see some solutions or explanations to solve this particular problem.

Regards

Hi coulet.
Thank you for the answer. Of course I've already seen the other threads similar to my case, but unfortunately I have not found the right solution for my case. I'll continue to search... :)

Hello,

Yes you need to know if your upstream with prescribed flowrate can be supercritical. If it is you need to prescribe also the elevation. Another solution is to change the bottom to have a larger depth at the entrance so that the flow is always subcritical.

With best regards,

JMH

Thank you for your answers.

To solve my problem I changed my liquid boundaries file. In fact the discharge after few seconds was too high (1000m3/s) and the river was not able to manage a such high value, causing the stop of the program. In fact it passed from 0 to 1000 m3/s in a moment. Putting low and growing discharges at the beginning, the problem is solved.

Hope it helps for the Telemac users of the future :)

Flavio