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Hello,
I have a problem with my Tomawac results when I use the coupling system Telemac2D/Tomawac.
In the attached file, you can see the different results in terms of significant wave height (in brown for Tomawac without coupling, in blue for Tomawac coupled with Telemac, grey crosses are in-situ data).



My time steps are (for the coupled simulation):
- 10 s for Telemac
- 10 s for Tomawac
- a coupling period of 60 (call every 10 minutes).
My time step for Tomawac only is 300 s.

Does someone have an idea of what happens ?

Thanks
Franc

PS: current velocities are very high in my area of interest.

Hello,

if you impose the same time steps for Telemac and Tomawac (10s in your case), then you have to set COUPLING PERIOD FOR TOMAWAC equal to 1.

Please, refer to the TOMAWAC guide (Chapter 8.2.7 - Waves-current interactions: direct coupling with Telemac (2D or 3D) flow simulation) for more information concerning the direct coupling TOMAWAC-TELEMAC

Kind regards,

Giovanni

Hello,

I have read again the user manual and so I have modify my time steps to have a "correct" coupling.
(And thank you for the reply Giovanni)
My new time steps are:
- 10 s for Telemac
- 360 s for Tomawac
- a coupling period of 36 (call every 6 minutes).
In the attached file, you can see the different results in terms of significant wave height (in green for Tomawac without coupling, in blue for Tomawac coupled with Telemac with old time steps, in brown for Tomawac coupled with Telemac with old time steps, grey crosses are in-situ data).



So, it's better with new time steps but the effect of current on waves remains too high.
Does someone have an idea on how to miniminize this effect?

Thanks
Francois

Hello,

have you chacked the results you get when using the coupling and a 10s time step for TOMAWAC ?

Pay attention when you set the TOMAWAC time step : the Courant number for the smallest mesh size should not be larger than 2.

Courant number = group velocity * time step / mesh size

Regards,

Giovanni