Progress in Turbulence and Wind Energy IV pp 263-270 | Cite as
Lidar Turbulence Measurements for Wind Energy
Abstract
Modeling of the systematic errors in the second-order moments of wind speeds measured by continuous-wave (ZephIR) and pulsed (WindCube) lidars is presented. These lidars use the velocity azimuth display technique to measure the velocity vector. The model is developed for the line-of-sight averaging and the full extent of conical scanning. The predictions are compared with the measurements from the ZephIR, WindCube and sonic anemometers at a flat terrain test site, under different atmospheric stability conditions. It is observed that the systematic errors are up to 90% for the vertical velocity variance, whereas they are up to 70% for the horizontal velocity variances. The systematic errors also vary with atmospheric stability, being lowest for the very unstable conditions. It is concluded that with the current measurement configuration, these lidars cannot be used to measure turbulence precisely.
Keywords
Wind Turbine Wind Energy Sonic Anemometer Turbulence Measurement Atmospheric Stability ConditionPreview
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References
- 1.Smith, D.A., Harris, M., Coffey, A.S., Mikkelsen, T., Jørgensen, H.E., Mann, J., Danielian, R.: Wind lidar evaluation at the Danish wind test site in Høvsøre. Wind Energy 9, 87–93 (2006)CrossRefGoogle Scholar
- 2.Kindler, D., Oldroyd, A., Macaskill, A., Finch, D.: An eight month test campaign of the QinetiQ ZephIR system: Preliminary results. Meteorologische Zeitschrift 16(5), 479–489 (2007)CrossRefGoogle Scholar
- 3.Courtney, M., Wagner, R., Lindelow, P.: Testing and comparison of lidars for profile and turbulence measurements in wind energy. In: 14th International Symposium for the Advancement of Boudary Layer Remote Sensing (2008)Google Scholar
- 4.Peña, A., Hasager, C.B., Gryning, S.-E., Courtney, M., Antoniou, I., Mikkelsen, T.: Offshore wind profiling using light detection and ranging measurements. Wind Energy 12(2), 105–124 (2009)CrossRefGoogle Scholar
- 5.Engelbart, D.A.M., Kallistratova, M., Kouznetsov, R.: Determination of the turbulent fluxes of heat and momentum in the ABL by ground-based remote-sensing techniques (a review). Meteorologische Zeitschrift 16(4), 325–335 (2007)CrossRefGoogle Scholar
- 6.Emeis, S., Harris, M., Banta, R.M.: Boundary-layer anemometry by optical remote sensing for wind energy applications. Meteorologische Zeitschrift 16(4), 337–347 (2007)CrossRefGoogle Scholar
- 7.Sjöholm, M., Mikkelsen, T., Mann, J., Enevoldsen, K., Courtney, M.: Spatial averaging-effects on turbulence measured by a continuous-wave coherent lidar. Meteorologische Zeitschrift 18(3) (Sp. Iss. SI) , 281–287 (2009)CrossRefGoogle Scholar
- 8.Mann, J., Cariou, J., Courtney, M., Parmentier, R., Mikkelsen, T., Wagner, R., Lindelow, P., Sjöholm, M., Enevoldsen, K.: Comparison of 3D turbulence measurements using three staring wind lidars and a sonic anemometer. Meteorologische Zeitschrift 18(2) (Sp. Iss. SI), 135–140 (2009)CrossRefGoogle Scholar
- 9.Mann, J., Peña, A., Bingöl, F., Wagner, R., Courtney, M.S.: Lidar scanning of momentum flux in and above the surface layer. Journal of Atmospheric and Oceanic Technology 27(6), 792–806 (2010), doi:10.1175/2010JTECHA1389.1CrossRefGoogle Scholar
- 10.Sathe, A.R., Mann, J., Gottschall, J., Courtney, M.: Estimation of the systematic errors in lidar turbulence measurements. To be published in JTECH (2011)Google Scholar
- 11.Mann, J.: The spatial structure of neutral atmospheric surface-layer turbulence. Journal of Fluid Mechanics 273, 141–168 (1994)MATHCrossRefGoogle Scholar
- 12.Sonnenschein, C.M., Horrigan, F.A.: Signal-to-noise relationships for coaxial systems that heterodyne backscatter from atmosphere. Applied Optics 10(7), 1600 (1971)CrossRefGoogle Scholar
- 13.Monin, A.S., Yaglom, A.M.: Statistical Fluid Mechanics, vol. 2. MIT Press (1975)Google Scholar
- 14.Peña, A., Gryning, S.-E., Mann, J.: On the length scale of the wind profile. Quarterly Journal of the Royal Meteorological Society (2010) (accepted)Google Scholar
- 15.Eberhard, W.L., Cupp, R.E., Healy, K.R.: Doppler lidar measurements of profiles of turbulence and momentum flux. Journal of Atmospheric and Oceanic Technology 6, 809–819 (1989)CrossRefGoogle Scholar