ESTONIAN ACADEMY
PUBLISHERS
eesti teaduste
akadeemia kirjastus
cover
Estonian Journal of Engineering

Periodicity of the average wind shear; 65–75

Full article in PDF format

Authors
Teolan Tomson, Hannu Lamp

Abstract

Higher level wind speeds are traditionally predicted either on the basis of the widely used logarithmic equation or using the Hellmann equation. In both equations, a coefficient that assesses the average wind shear curvature is usually used. This coefficient has been considered to be a constant, depending on the roughness of the surrounding landscape. In this paper, on the basis of wind speeds, recorded at different heights, we show that this coefficient is not a constant but it varies periodically with a period close to one year.


References

  1. DeRenzo, J. (ed.). Recent Developments in Wind Power. Energoatomizdat, Moscow, 1982 (in Russian).

  2. Petersen, E. L., Landberg, L. and Mortensen, N. G. EU Wind Atlas, vol. II: Measurements and Modeling in Complex Terrain. Risø National Laboratory, Denmark, 1995.

  3. Lange, b., Højstrup, J. and Barthelmie, R. Evaluation of models for the vertical extrapolation of measurements at offshore sites. In Proc. EWEC2001 Conference. Dublin Castle, 1996, 834–837.

  4. Hansen, K. S., Larsen, G. C. and Courtney, M. Database on wind characteristics. In Proc. EWEC2001 Conference. Dublin Castle, 1996, 858–862.

  5. Tomson, T. Steady-state variability of the Estonian wind. Studies on Climate of Estonia. Publicationes Instituti Geographici Universitatis Tartuensis, 2003, 93, 206–216.

  6. Tomson, t. and Bergström, H. Periodical effects in the Baltic Proper. In Proc. Conference OWEMES2003. Naples, 2003. CD-ROM, 11 p.

  7. Tomson, T. and. Nõva, A. Geographically distributed wind turbines on the West-Estonian coast. Agricult. Eng. Internat., CIGR J. Sci. Res. Developm., 2001, 3, Manuscript EE00 006, 9 p.

  8. Tomson, T. Periodical component of the West Estonian wind. Proc. Estonian Acad. Sci. Eng., 2001, 7, 50–57.

  9. Ronsten, G., Thor, S.-E., Ganander, h. et al. Evaluation of loands, power quality, grid interaction, meteorological conditions and power performance of the first Swedish offshore wind farm at Bockstigen. In Proc. Second international Workshop on Transmission Networks for Offshore Wind Farms. Royal Institute of Technology, Stockholm, 2001, 1(17)–17(17).

10. Tomson, T. and Hansen, M. Seasonal wind stability on the West Estonian coast. Proc. Estonian Acad. Sci. Eng., 2001, 7, 212–221.


Back to Issue