Mr. Coulet
Thank you for your response.
In my case I only tested the example given when downloading télémac2d. in the validation file, there is a "Bridge" exemple.
In the "cas" file, the initial side is 7m, and prescribed elevations 7m, 7m.
When Simulating the tube switch from free flow area to close-driven flow
and level deph in upstream becomes 9m.
For buse.f file, I confess I do not know FORTRAN, but I wrote a routine in vb dot net that allows me to calculate the hydraulic capacity of a tube.
I can only see that the flow in the tube is overestimate by buse.f routine!