Experiments in Fluids

, 58:1 | Cite as

Measurement of unsteady loading and power output variability in a micro wind farm model in a wind tunnel

  • Juliaan BossuytEmail author
  • Michael F. Howland
  • Charles Meneveau
  • Johan Meyers
Research Article


Unsteady loading and spatiotemporal characteristics of power output are measured in a wind tunnel experiment of a microscale wind farm model with 100 porous disk models. The model wind farm is placed in a scaled turbulent boundary layer, and six different layouts, varied from aligned to staggered, are considered. The measurements are done by making use of a specially designed small-scale porous disk model, instrumented with strain gages. The frequency response of the measurements goes up to the natural frequency of the model, which corresponds to a reduced frequency of 0.6 when normalized by the diameter and the mean hub height velocity. The equivalent range of timescales, scaled to field-scale values, is 15 s and longer. The accuracy and limitations of the acquisition technique are documented and verified with hot-wire measurements. The spatiotemporal measurement capabilities of the experimental setup are used to study the cross-correlation in the power output of various porous disk models of wind turbines. A significant correlation is confirmed between streamwise aligned models, while staggered models show an anti-correlation.


Wind Tunnel Wind Turbine Turbulence Intensity Turbulent Boundary Layer Wind Farm 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



The authors would like to thank Adrien Thormann for his contributions to the hot-wire measurements. Work supported by ERC (Grant No. 306471, the ActiveWindFarms Project) and by NSF (Grants CBET-113380 and OISE-1243482, the WINDINSPIRE Project).


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Copyright information

© Springer-Verlag Berlin Heidelberg 2016

Authors and Affiliations

  1. 1.Department of Mechanical EngineeringKU LeuvenLeuvenBelgium
  2. 2.Department of Mechanical EngineeringJohns Hopkins UniversityBaltimoreUSA
  3. 3.Department of Mechanical Engineering, Center for Environmental and Applied MechanicsJohns Hopkins UniversityBaltimoreUSA

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