Davenport wind spectrum

The Davenport wind spectrum is given by

\[S(f, z)=\frac{4\kappa\bar{u}_r^2r^2}{\omega (1+r^2)^{4/3}}\]

where

\(\omega\)

angular frequency, \(\omega = 2\pi f\)

\(r\)

\(\displaystyle = \omega \frac{L_r}{2 \pi \bar{u} (z)}\)

\(L_r\)

reference length of wind turbulence (\(1200 ~ \mathrm{m} - 1800 ~ \mathrm{m}\) suggested)

\(\kappa\)

surface drag coefficient (\(0.001 - 0.003\) suggested)

Recommended values of \(\mathrm {L_r}\) and \(\mathrm {\kappa}\) can be found in (Sigbjørnson, 1977).