WInd Farm Model / Registry (2005-10-07)

[Old Forum Archivist]

Hi Wasp team,



if the wind vertical profile is defined with the formula:

V = Vref ( ln(h/z0) / ln(href/z0))

where z0 is the roughness length,

why, for a given z0, the mean wind speeds given by the Wasp atlas do not match with the formula ?

Thank you

Regards



P.Dauguet

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You can see the same thing when plotting the predicted wind profile over flat uniform terrain: the WAsP wind profile does not follow the logarithmic law exactly. This is caused by the fact that WAsP employs a simple stability correction, based on the mean and RMS values of the heat flux values over land and sea. If you 'kill' this stability correction - by setting the heat flux parameters to zero - the wind profile should be logarithmic.



The default heat flux values in WAsP were chosen as part of the analyses leading to the European Wind Atlas. In general, one could choose values that are representative of the site/region in question.



The WAsP Team

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