open TELEMAC-MASCARET The mathematically superior suite of solvers

Hi there,

I know its possible to include a weir in a Telemac model. I would like to know if Telemac can be of any use in determining the stage-discharge relationship of a weir that is not at 90 degrees with the flow.

Thanks!

Hello,

It has been designed for any angle, there is a velocity normal to the weir, that is subject to the weir law, and a transversal velocity.

Regards,

Jean-Michel Hervouet

Thanks!

If I may, I would like to ask you another question: does the weir law included in telemac can take into account downstream effect on the weir capacity? If so, is their any recommendation on the limit of validity when downstream levels are increased?

Many thanks

Hello,

Yes, there are 2 weir laws, one with downstream effect and the other without, and depending on upstream and downstream elevations, one of them is chosen.

With best regards,

Jean-Michel Hervouet

Hello

Have a look at the user manual, and exactky at the section dedicated to weir, there, you will find the full descriptions of the weir laws.

with my best regards
Riadh

Thanks Riadh for the hint.

I looked at the french version and english version of the user manual. The equation under "The weir is not submerged if:" is different in the two manuals. What is the equation implemented in telemac? (or in which .f files can we find the answer?).

Should it be y1 > 2/3 y2, where y1 is u/s water level - weir crest, and y2 is d/s water level - weir crest?

Hello

you are right there is an unconsistency between the english and the french manuals. The right formula is:
The weir is sugmerged if Hdownstr >2/3 Hupstr
I will fix this typo in the manual.

with my best regards

Riadh