open TELEMAC-MASCARET The mathematically superior suite of solvers

Hello,
It seems to me that an f**-5 term is missing in the Jonswap spectrum formula in chapter 4.6 of the Artemis 8.4 documentation. Without it, the spectrum is very irregular for higher frequencies. I have identified a jonswap function in the check spectrum.py code and I am pleased to see that the f**-5 term is indeed present. However, the spectrum formulation is not consistent with chapter 4.6. So I'd like to know which formula to use. In deed, I'm trying to calibrate the GAMMA and S EXPONENT parameters as well as possible, based on spectrum readings from the Candhis in the Mediterranean.

Regards
Yannick

Hello Yannick,

Thanks for pointing this issue.
I am not a wave specialist but reading the TOMAWAC user manual (section 8.4), there is the factor f**-5.
Moreover, I think alpha should be replaced by sigma.

I will ask some colleagues of mine who better know about wave to confirm.

Chi-Tuan

Hello Yannick,

Sorry for the delay, I can confirm that it was a mistake.
It has been fixed in release v8p5r1 (released mid-November 2024) and for next release 9.0 (coming very soon!).

Enclosed the modified page.

Thanks for having pointed this mistake.

Chi-Tuan