open TELEMAC-MASCARET The mathematically superior suite of solvers

Good morning,

I'm making some tests with tomawac (these are my first experiences with this modules).

I created three tanks with only one open boundary (see Vascona_BC attached file)

1) BOTTOM = 100 m, deep water
2) BOTTOM = 10 m, intermediate water
3) BOTTOM = 4 m, shallow water

I give in entry the same constant spectrum (Type 6 with Hs = 0.5 m, Tp = 8 s)for all of the thanks.

What I do not understand is why for all the three cases the results are exactly the same (see attached figure).

What I'm mistaking??

I attach the cas file of the shallow water (it's the same of the other)


Thanks for the attention,

Andrea

Hello

Can you also attach the geometry files that i can test them to understand what's happening ?

regards

T.

Thanks a lot for the reply,

I attach the geometries of the three cases.

Regards,

Andrea

hello andrea,

In your case there are mainly 2 consequences of the change of bathymetry, the waves celerity and the depth breaking.

Since you are treating a static case and watch the result at the end of convergence you can't see that one case arrived before the converged state but if you look at some time when it is not yet converged you will see it.

As for breaking, firstly you have to set
CONSIDERATION OF SOURCE TERMS = YES
otherwise you do not calculate depth breaking. And you also have to give BC to have breaking for example a wave height of 3 m.

Following are some advice i would give you seeing your steering file.

As for your frequency discretisation, if you look at the documentation you will see that Fn = F0* r**n so if you choose r=2 and n=70 you will have frequencies until 5.e20, usually it is better to have r=1.1 and n=30 that is less calculation for the same result.

Concerning the number of time steps, check how long it takes to converge: you chose 1000 time steps when 200 were sufficient.

You can also check if a coarser mesh would give same result, because i think yours might be too fine and then cost too much.

I join an example of modifications on your steering file.

Hope it helps

regards.

Thank you so much for the advices, I really appreciate it.

I knew that the mesh is very fine (even too much) and also the time steps are too much, but it was just for starting to investigate the module of tomawac and take some sensibility on it.

I will try your advices and let you know if some problems appear.

Thanks again for the accurate answer.

Regards,

Andrea