open TELEMAC-MASCARET The mathematically superior suite of solvers

Hello, I am a new user of the software, I'm trying to learn how to use the form TOMAWAC.
I want to find wave height in the computational domain considered that is generated solely as a result of a steady wind constantly imposed. The wave spectrum I would take zero to evaluate only the wave height that comes as a result of wind only.
Using keywords in the Annex, trying to change the speed of the wind I get a wave height is always the same; it is as if he resented the change in the wind that impose.
Can someone kindly risolvermi these two questions:
1) How do I completely reset the spectrum and consider only the wind as the source of the wave?
2) What keywords should I change to simple stationary force winds in varying degrees?

KEYWORDS MODIFIED:

ABSCISSAE OF SPECTRUM PRINTOUT POINTS 7244
BOUNDARY ANGULAR DISTRIBUTION FUNCTION 3
BOUNDARY CONDITIONS FILE cas.conlim
BOUNDARY MAIN DIRECTION 1 220
BOUNDARY MAXIMUM PEAK FREQUENCY 0.3
BOUNDARY MEAN FETCH VALUE 150000
BOUNDARY PEAK FREQUENCY 0.3
BOUNDARY SIGNIFICANT WAVE HEIGHT 2
CONSIDERATION OF A WIND true
FREQUENTIAL RATIO 1.3
GEOMETRY FILE geo11
INITIAL ANGULAR DISTRIBUTION FUNCTION 3
INITIAL MAIN DIRECTION 1 220
INITIAL MAXIMUM PEAK FREQUENCY 0.3
INITIAL MEAN FETCH VALUE 150000
INITIAL PEAK FREQUENCY 0.3
INITIAL SIGNIFICANT WAVE HEIGHT 2
MINIMAL FREQUENCY 0.07
NUMBER OF FREQUENCIES 19
NUMBER OF TIME STEP 1000
ORDINATES OF SPECTRUM PRINTOUT POINTS -42936
PERIOD FOR GRAPHIC PRINTOUTS 10
PERIOD FOR LISTING PRINTOUTS 10
TIME STEP 5
TITLE Prova_CON VENTO
TYPE OF BOUNDARY DIRECTIONAL SPECTRUM 2
TYPE OF INITIAL DIRECTIONAL SPECTRUM 6
VARIABLES FOR 2D GRAPHIC PRINTOUTS HM0,DMOY,VX,VY,FX,FY
WIND GENERATION 1
WIND VELOCITY ALONG X -5
WIND VELOCITY ALONG Y -10

I hope for your help
regards

Luca

Hello

You should find the answer of your questions in the description of the function of your keywords from Page 74 to page 110.
For example
TYPE OF BOUNDARY DIRECTIONAL SPECTRUM
TYPE OF INITIAL DIRECTIONAL SPECTRUM
will certainly help

regards

T.

Thanks so much. I tried to reset the spectrum considering only the wind, but the significant wave I is everywhere zero. Why is this happening? Why not read me file of wind?

please help me
regards

Luca

Hi Luca,

If boundary spectrum is null, then you have to set LINEAR WAVE GROWTH=YES. This enables wave to grow from zero.

Regards,
Costas

Thanks so much. There is one other thing I do not understand. Keeping constant the wind, I discretized so oppurtuno the spectrum on the basis of the frequencies. How do I increase or decrease the amount of spectrum that flow into the domain in order to assess the wave height?

I hope in your help
regards

Luca

You could select a boundary spectrum type that takes into consideration the fetch length outside your domain. The larger the fetch the larger the wave energy that enters your domain.

Although, I am not sure I have understood the question correctly... Please elaborate more on your objectives.

Regards,
Costas

Thanks of the interest. I wanted to keep a steady wind (and therefore fetch consider constant) input to the computational domain which provides energy to the wave.
I would speculate that there is a spectrum of initial (besides the wind) input to the computational domain which provides energy to the wave. How do I increase or decrease this spectrum?

I hope for your help
Regards

Luca

If you want to accurately define the boundary spectrum, then there are many ways to do so by defining the boundary conditions. Have a look at Table 8.1, page 66 of the TOMAWAC manual. It explains all available boundary spectrums. Some depend on wind, some do not. Does that help?

Costas

Thanks so much. I'm sorry but I'm new in TELEMAC and am trying to learn how it works.
I took in condireazione the following keywords referring to the type of spectrum:
TYPE OF BOUNDARY DIRECTIONAL SPECTRUM 2
TYPE OF INITIAL DIRECTIONAL SPECTRUM 6

If I keep the type of the spectrum constant and even the wind would consider constant, how do I aumnetare or decrease the energy transferred to the wave?

Do I need to change these two keywords ?:
BOUNDARY SIGNIFICANT WAVE HEIGHT 2
INITIAL SIGNIFICANT WAVE HEIGHT 2

I hope for your help
Regards

Luca

Hi Luca,

I don't understand what you mean "energy transferred to the wave". You just want to increase the wave weight or you want to increase the energy that is transferred from a steady wind to the wave? If it is the latter, then you can adjust the variables for WIND GENERATION (see paragraph 8.3.2.1 of the tomawac manual).

Regards,
Costas