open TELEMAC-MASCARET The mathematically superior suite of solvers

We have tomawac model coupled with telemac2d and when we try the COUPLING PERIOD OF TOMAWAC = 120, Tomawac didn't give results, it only works if it is = 1, but it's too slow.
Is anyone know the reason?

Hello,

When you couple Telemac2D with Tomawac, the timestep for Tomawac is (telemac2d timestep)x(Coupling period of Tomawac). In your case that would be 120x5=600 seconds, which is a very large timestep considering you include wave breaking that requires a timestep in the order of 1s. If you set the coupling period to 120, then you will have to introduce sub-steps for the source terms and breaking. However, this will also increase the computation time, so there isn't a lot to gain.

Regards,
Costas

thanks
we solved it

Hello Costas,

I have a similar question. I couple T2d-Tomawac-Sisyphe and it does not matter which coupling period i choose, the calculation time step for the model is always the time step which is written in the Tomawac .cas file.
I wonder if this is kind of a standard or if I make something wrong. Moreover, the simulation stops after a while and demands for a smaller time step.

Actually I like to have the following time steps
T2d: 4sec
Tomawac: 2sec
Sisyphe: 10sec

If i follow your explanation this seems not possible to couple it in this way, am I right?

Regards,
Clemens

Hi Clemens,

You can have a look at the section 8.2.7 of tomawac user manual. The simulations must have the same time length (time steps * number of time steps) as well as equal or multiple time steps of each other. You'll also find specifications for the coupling period.

I hope it helps.
Laurent

Hello,

is there a possibility or a way to recover the results file after an interruption of the simulation? or to start the simulation again from where it stopped?

best regards