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Hello everyone!
In my model I have 2 liquid boundaries: on is of prescribed elevation and the other one is prescribed discharge.
I noticed from the sortie file that the flow through the prescribed discharge boundary does not match with the value of discharge that I prescribed (see picture).

In my liquid boundaries file I prescribed Q in m3/s. Indeed, header lines are:
T SL(1) Q(2)
s m m3/s

I dont't get why it is changed in that way. Thank you very much for your time.

Hello Giulia,

Which release do you use?
Can you upload at least your steering file, potential user Fortran files + boundary conditions file please?

Chi-Tuan

Hey!
I use v8p4 version. I attach my files
Thank you for your time!
Giulia

Hello Giulia,

You use OPTION FOR LIQUID BOUNDARIES = 2;2 i.e.Thompson method to compute boundary conditions. That means that Riemann invariants are computed for boundary conditions instead of prescribing values such as flowrates or water depths. That explains why the value written in the listing file is not the same as what you thought you prescribe.

You can try to let default choice for OPTION FOR LIQUID BOUNDARIES = 1;1. You should then retrieve what you expected in the listing file.

Hope this helps,

Chi-Tuan

Thank you so much!