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Hi,

I'm working on a simple model and I'm regarding the influence of wind.

I have realized a simple simulation without wave as initial condition. I impose a stationary wind and I see it is well integrated in the model looking at VX and VY in Fudaa.

The model generates wave only if I put the key word LINEAR WAVE GROWTH = 1. After reading the manual, I understand this parameter add a source term and for me without this option waves should still be generated. Am I wrong? Have I forgotten something?
My parameter file is in attachment.



Regards

Hello Nicolas,

The option LINEAR WAVE GROWTH is necessary for wind waves to be generated when the boundary wave conditions are 0, e.g. when modeling a lake.

From the TOMAWAC manual( paragraph 4.2.3.2):
I hope it helps.

Regards,
Costas

Edit:

OK, I have seen your cas file and you have not set any boundary conditions, so LINEAR WAVE GROWTH should work for you.

Can you try uncommenting theline and try again?

Hello Costas,

Ok for the manual.

My model have only boundary type 2, so key words type "boundary" are useless I think.

I have tried to set LINEAR WAVE GROWTH to 0 with initial condition non equal to zero. I have the waves expected at the first time step (Hs=0.5m) but during the simulation, the waves are decreasing to 0 whereas the wind is strong (141km/h). I have checked in Fudaa, the wind is well taken account.

So I am a little doubtful about this key word LINEAR WAVE GROWTH...

Here is my parameter file :



Regards

It seems strange that you don't get any wind generation. If you send the geometry and cli files I could have a look...

Costas

Here is the cli and the geo file.







Regards.

Just checked with the first cas file you have posted and I get a wave height of about 2.7-2.8m at the Southeast limit of the model. Is that what you would expect?

Costas

Edit:
Here is a screenshot of the results:

I have strange results with the parameter file posted today : Fr_cotier_2014-09-02.cas
The result you have just sent is it computed with it?
It is just a test to check the influence of LINEAR WAVE GROWTH so I expect to have some waves but no values in particular.

Regards

I used Fr_cotier.cas file. Fr_cotier_2014-09-02.cas starts with 0.5m wave height in the domain, which in subsequent steps decays to 0. Setting LINEAR WAVE GROWTH to 1 yields similar results at the end. No problem at my side...
Costas

Maybe we are misunderstanding.
I'm using the case file Fr_cotier_2014-09-02.cas.
If I set LINEAR WAVE GROWTH to 0, the waves are decreasing from 0.5 to 0.
If I set LINEAR WAVE GROWTH to 1, the waves are increasing from 0.5 to 2.8 at the boundary (maximum).

As it is described in Tomawac manual, it seems to me that LINEAR WAVE GROWTH = 1 is not compulsory to generate wave but that it is what I see with this test!

OK I see your point. The manual is not clear but as I understand it, LINEAR WAVE GROWTH is compulsory when boundary spectrum is nil, not the initial. This way your results are explained.

Costas