Boundary-Layer Meteorology

, Volume 87, Issue 3, pp 459–480 | Cite as

Horizontal, Two Point Coherence for Separations Greater Than the Measurement Height

  • Wolfgang Schlez
  • David Infield


Wind speed measurements from the test site at Rutherford Appleton Laboratory have been evaluated with respect to the spatial coherence function. The experimental arrangement provides coherence information for separation distances of 62, 80 and 102 m. These are at least three times greater than the measurement heights of 18 m and 18.7 m. Based on these experimental data and data published in the literature, different theoretical formulations are compared and a new, but simple, model for longitudinal and lateral coherence is proposed. At large separations the turbulent wind field is not isotropic, theoretical models to describe the coherence function for such distances are not available. The new model we propose builds on the classical exponential approach. It takes into account the influence of turbulence intensity and models the angular dependence of horizontal coherence. It is found that, for constant turbulence intensity, the lateral coherence decay becomes independent of the mean wind speed.

Coherence model Spatial coherence Turbulence 


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Copyright information

© Kluwer Academic Publishers 1998

Authors and Affiliations

  • Wolfgang Schlez
    • 1
  • David Infield
    • 1
  1. 1.Centre for Renewable Energy Systems Technology (CREST), Department of Electronic and Electrical EngineeringLoughborough UniversityUnited Kingdom

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