open TELEMAC-MASCARET The mathematically superior suite of solvers

I decided to change atmospheric pressure in the whole domain but nothing change. I have the same result than before without "pression atmosphérique = OUI".
Maybe I have to change an other thing to see the effect of pressure.I just changed P0 in the subroutine et I put Yes with Pression atmosphérique. I thought my depth water would increase if I put a lower pressure but nothing changes.
If someone can explain me how to see the effect of pressure or how telemac2d works with atmospheric pressure.

Regards,
J. BAILLS

Hi

As you change only the value, the result is logical.

As indicated in the Jean-Michel books and probably also in the users manuals, this is the derivative in space which is added to the momentum equation. If the value is constant in space, the derivative in space is zero...

To see the pressure effect, you should describe the spatial variation and eventually the temporal variation.

Regards

Thank you for your quick answer.
I thought pressure in saint venant equation depended of atmospheric pressure and spatial derivation too. I thought that if I changed the value of the atmospheric pressure, pressure would change and results would change.
I'm a little embarassed with this problem, I don't know how to manage with the derivative in space with my problem.
Because atmospheric pressure is the same in my whole domain and I do simulation in an estuary during one tide or 2 max. And I want to change climate to see the difference of the resulst given by my simulation. In fact, I don't understand how can I have spatial variation of pressure in a little domain.

Regards

I understand your problem but let me explain the problem differently.

If you run two simulations, with the same downstream boundary condition, but with two different constant pressure... You expect the result change between the simulations. But this leads another question (problem?)
Normaly, the level imposed at the downstream boundary condition should also be affected by the change of the pressure.
So in fact, your expectation gives some inconsistencies between the boundary and the model...

In fact, if your domain is limited, the pressure effect will mainly drive the water level at the downstream boundary so you could take in account the pressure effect by a simple mean sea level variation estimate by the inverse barometric method

Hope this helps

In fact, if I want to change atmospheric pressure, I have to change the level imposed in my boundary conditions.
Thank you a lot for all your explanations and for the time you took to help me.