Probability distribution for winds in WAT

[Petar]

Hello,

I have noticed that the 'p(u)':the probability distribution for winds from all directions in the WAT 'Wake turbulence' output file is not the same as the 'p(u)_IEC':IEC reference probability distribution, I have used IEC wind class III for the comparison (A & k factor). Please explain me, why is this so ?

Thank you in advance and Best Regards
Petar

[Morten]

Hi Petar,


'p(u)' is our modelled site-specific wind speed distribution based on the Wind Atlas *.lib file you provide when setting up the WAT project.

'p(u)_IEC' is a turbine-specific wind speed distribution determined by the IEC turbine class. The combination of this distribution and some standard models for turbulence and wind shear was used by the manufaturer to verify turbine safety with respect to fatigue damages. For the site assessment we may assume safe turbine deployment when on-site turbulence intensity and wind-speed probability density are lower in the range of turbine operation that assumed for the turbine-classification load cases.

Read more about this in the WAT help file or, better, in the IEC 61400-1 standard.


Cheers,
Morten