Sponsor
This work is in part funded by the National Science Foundation (Grant No. CBET-1034581).
Published In
Journal of Renewable and Sustainable Energy
Document Type
Article
Publication Date
2-12-2016
Subjects
Boundary layer, Wakes (Aerodynamics), Wind turbines -- Aerodynamics
Abstract
Hot-wire measurements obtained in a 3 × 3 wind turbine array boundary layer are utilized to analyze high order structure functions, intermittency effects as well as the probability density functions of velocity increments at different scales within the energy cascade. The intermittency exponent is found to be greater in the far-wake region in comparison with the near-wake. At hub height, the intermittency exponent is found to be null. Extended self-similarity scaling exponents of the second, fourth, and fifth order structure functions remain relatively constant as a function of height in the far-wake; whereas in the near-wake, these are highly affected by the passage of the rotor where tip vortices reside, thus showing a dependence on physical location. When comparing with proposed models, these generally overpredict the structure functions in the far-wake region. The probability density function distributions in the far-wake region display wider tails compared to the near-wake region, and the constant skewness hypothesis based on the local isotropy is disrupted in the wake.
DOI
10.1063/1.4941782
Persistent Identifier
http://archives.pdx.edu/ds/psu/16696
Citation Details
Ali, N., Aseyev, A. S., & Cal, R. B. (2016). Structure functions, scaling exponents and intermittency in the wake of a wind turbine array. Journal of Renewable and Sustainable Energy, 8(1), 013304.
Description
Reprinted with Author and Publisher permissions. The definitive version can be found at the publisher site.
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