Wind Energy

Height [m]
100
90
80
70
60
50
40
30
5 Wind Speed Profiles above the North Sea 31
1% 16% 30% 18% 14% 11% 4% 2% 1% 1%
unstable conditions: u(51m)/u(33 m) < 1.04
neutral conditions
stable conditions: u(51m)/u(33 m) > 1.06
log. profile z0 = 0.2 mm
IEC−61400−3
IEC−61400−1
0.9 1 1.1 1.2 1.3 1.4 1.5
Mean wind speed normalised to u(33 m)
Fig. 5.3. Profiles and frequencies of different classes of thermal conditions at FINO1
we use the single wind shears between 33 and 51 m height to calculate Φm in
order to provide the ICWP-model with information about the stability of the
atmospheric stratification, the RMSE is reduced to 3.6% at 103 m height.
References
1. J.A.T. Bye. Inertial coupling of fluids with large density contrast. Phys. Lett.
A, 202:222–224, 1995
2. J.A.T. Bye. Inertially coupled Ekman layers. Dyn. Atmos. Ocean, 35:27–39,
2002
3. J. Tambke, J.A.T. Bye, M. Lange, U. Focken, and J.-O. Wolff. Forecasting Offshore
Wind Speeds above the North Sea. Wind Energy, 8:3–16, 2005