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Hi all,

I'm trying to generate the current field due to wind wave near a delta in Lake Geneva. Tomawac alone give accurate results. I however encounter problem regarding to an "artificial" current generation in the lake area while coupling with TELEMAC. This is due, I think to bathymetric gradient between the east and the west side of my domain as you can see in the followings figures :





You will find also here under my .cas file for the TOMAWAC part of the model :


And my BC file :


Did you see a way to fix the problem ?

In case you need it, hereunder is the .cas file for telemac :


Best regards,
Alexandre Fourrier

Hello,

Sorry but i do not understand what are on your figures. Can you explain what is the result of what (tomawac/telemac) and what variable you are showing.

I think that to make us fully understand you should post all your files, it is difficult to have an idea with just 2 steering files.

Kind regards

Hello Alexandre,
According to your Telemac steering file, one of your boundaries has a higher elevation than the other (by 14m!). So it is expected to have water flowing steadily from the higher elevation to the lower.

Costas

Hello all,

First thank you for your answer.

Here is a brief description of my model,I coupled Telemac-2d, Sisyphe and Tomawac in order to better understand the process and the parameters influencing lacustrine delta morphology. I increase the complexity of my model step by step. First, I run telemac-2d alone giving me accurate results then, I try the coupling with sisyphe. The results were also satisfaying that is why I tried the coupling with Tomawac.
I have a liquid boundary file with prescribed discharge at my river inlet (~386 m AMSL)and an open boudary at the level of the Lake Geneva(~372.10 m AMSL)with prescribed elevation.
To simulate wave, I use as boundary condition the website swisslake.net where for different wind conditions and return period, the wave height, period and length are given such that Tomawac computes only the wave dissipation.

In the figure in my previous post, in the first one is represented the bottom elevation of my domaine with the wave force (tomawac simulation alone). In the second one is represented the coupling between telemac, tomawac and sisyphe. The surrounded part of the figure correspond to the "artificial" current geenrated in my domain.

I hope these explanation helps for the understanding of my problem. Hereunder are my .cas file, geometry file and BC file for telemac, sisyphe and tomawac :

Telemac-2d :







Sisyphe :





(same geometry than for telemac)

Tomawac :





(same geometry than for telemac)

Hereunder is a link to the other necessary files (fortran subroutine et liquid boundary file) for launching the simulation : grosfi.ch/cFdcu29S39R

Best regards,
Alexandre

Hello

I did the simulations with coupling with telemac (did not couple with sisyphe something is not working with sisyphe steering file) but it seems that i do not have the same behaviour as you got.

you will see the result obtained with or without the coupling in the pictures joined.

Seeing what you have in your steering file you are using an old version of telemac (may be V8.0) you should try with a recent one (V8.3 for example) may be that a bug has been fixed meanwhile.

kind regards

Thierry

Hello,

Thank you very much for your answer. So I will try with the new version. Just by curiosity, does it take long time for you to compute also with your computer ? Do you have any advice to reduce computation time ?

Before installing the new version, if you have some time, can you please print the velocity in telemac because it is mainly in the velocity field while coupling that I have mess that occurs offshore in the lake ?

Best regards,
Alexandre

- Here is the result with the full coupling (there was a problem with sisyphe in src_source_sis_2002.txt replace QG(2) by QG(1) )

- It takes 18 minuts in sequential, i do not see advice to reduce time without having a lower quality result.

- In aubonne_steady_state_V2.cas, you can't have HM0,TMOY,DMOY as an output, ask it in tomawac file.

- My colleague, Pablo Tassi, told me that your option in sisyphe is not good in a coupling case with tomawac.
add EFFECT OF WAVES = YES
and change the transport formula for example 5

- I also add the velocity result.

Hello,

Thank you very much for your answer and advice, I will try then whith these parameters to obtain sediments re-working.
I will keep you informed of the progress and of the obtained results.

Best regards,
Alexandre

Hello all,

I finally get rid of this current by playing with my BC and obtain results in line with previous studies.
In condition of "Vent" which is a wind coming from West, I just set the boundary in the West boundary of my domain as a BC with prescribed elevation. The other one were set to free boundary absorbing wave energy.
In condition of Bise which is a wind coming from East, I have set the eastern boundary of my domain to a BC with prescribed elevation and the other one as free boundary.

Hope this message can help and thank you again to all of you for your answers.

Best regards,
Alexandre