Three-dimensional structure of wind turbine wakes as measured by scanning lidar
The lower wind speeds and increased turbulence that are characteristic of turbine wakes have considerable consequences on large wind farms: turbines located downwind generate less power and experience increased turbulent loads. The structures of wakes and their downwind impacts are sensitive to...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
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Copernicus Publications
2017-08-01
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| Series: | Atmospheric Measurement Techniques |
| Online Access: | https://www.atmos-meas-tech.net/10/2881/2017/amt-10-2881-2017.pdf |
| _version_ | 1828406257345626112 |
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| author | N. Bodini N. Bodini D. Zardi J. K. Lundquist J. K. Lundquist |
| author_facet | N. Bodini N. Bodini D. Zardi J. K. Lundquist J. K. Lundquist |
| author_sort | N. Bodini |
| collection | DOAJ |
| description | The lower wind speeds and increased turbulence that are characteristic of
turbine wakes have considerable consequences on large wind farms: turbines
located downwind generate less power and experience increased turbulent
loads. The structures of wakes and their downwind impacts are sensitive to
wind speed and atmospheric variability. Wake characterization can provide
important insights for turbine layout optimization in view of decreasing the
cost of wind energy. The CWEX-13 field campaign, which took place between
June and September 2013 in a wind farm in Iowa, was designed to explore the
interaction of multiple wakes in a range of atmospheric stability conditions.
Based on lidar wind measurements, we extend, present, and apply a
quantitative algorithm to assess wake parameters such as the velocity
deficits, the size of the wake boundaries, and the location of the wake
centerlines. We focus on wakes from a row of four turbines at the leading
edge of the wind farm to explore variations between wakes from the edge of
the row (outer wakes) and those from turbines in the center of the row (inner
wakes). Using multiple horizontal scans at different elevations, a
three-dimensional structure of wakes from the row of turbines can be created.
Wakes erode very quickly during unstable conditions and can in fact be
detected primarily in stable conditions in the conditions measured here.
During stable conditions, important differences emerge between the wakes of
inner turbines and the wakes of outer turbines. Further, the strong wind veer
associated with stable conditions results in a stretching of the wake
structures, and this stretching manifests differently for inner and outer
wakes. These insights can be incorporated into low-order wake models for wind
farm layout optimization or for wind power forecasting. |
| first_indexed | 2024-12-10T11:08:13Z |
| format | Article |
| id | doaj.art-e2feee78e5404823a63eec88896471db |
| institution | Directory Open Access Journal |
| issn | 1867-1381 1867-8548 |
| language | English |
| last_indexed | 2024-12-10T11:08:13Z |
| publishDate | 2017-08-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Atmospheric Measurement Techniques |
| spelling | doaj.art-e2feee78e5404823a63eec88896471db2022-12-22T01:51:30ZengCopernicus PublicationsAtmospheric Measurement Techniques1867-13811867-85482017-08-01102881289610.5194/amt-10-2881-2017Three-dimensional structure of wind turbine wakes as measured by scanning lidarN. Bodini0N. Bodini1D. Zardi2J. K. Lundquist3J. K. Lundquist4Department of Atmospheric and Oceanic Sciences, University of Colorado Boulder, Boulder, Colorado, USADepartment of Civil, Environmental and Mechanical Engineering, University of Trento, Trento, ItalyDepartment of Civil, Environmental and Mechanical Engineering, University of Trento, Trento, ItalyDepartment of Atmospheric and Oceanic Sciences, University of Colorado Boulder, Boulder, Colorado, USANational Renewable Energy Laboratory, Golden, Colorado, USAThe lower wind speeds and increased turbulence that are characteristic of turbine wakes have considerable consequences on large wind farms: turbines located downwind generate less power and experience increased turbulent loads. The structures of wakes and their downwind impacts are sensitive to wind speed and atmospheric variability. Wake characterization can provide important insights for turbine layout optimization in view of decreasing the cost of wind energy. The CWEX-13 field campaign, which took place between June and September 2013 in a wind farm in Iowa, was designed to explore the interaction of multiple wakes in a range of atmospheric stability conditions. Based on lidar wind measurements, we extend, present, and apply a quantitative algorithm to assess wake parameters such as the velocity deficits, the size of the wake boundaries, and the location of the wake centerlines. We focus on wakes from a row of four turbines at the leading edge of the wind farm to explore variations between wakes from the edge of the row (outer wakes) and those from turbines in the center of the row (inner wakes). Using multiple horizontal scans at different elevations, a three-dimensional structure of wakes from the row of turbines can be created. Wakes erode very quickly during unstable conditions and can in fact be detected primarily in stable conditions in the conditions measured here. During stable conditions, important differences emerge between the wakes of inner turbines and the wakes of outer turbines. Further, the strong wind veer associated with stable conditions results in a stretching of the wake structures, and this stretching manifests differently for inner and outer wakes. These insights can be incorporated into low-order wake models for wind farm layout optimization or for wind power forecasting.https://www.atmos-meas-tech.net/10/2881/2017/amt-10-2881-2017.pdf |
| spellingShingle | N. Bodini N. Bodini D. Zardi J. K. Lundquist J. K. Lundquist Three-dimensional structure of wind turbine wakes as measured by scanning lidar Atmospheric Measurement Techniques |
| title | Three-dimensional structure of wind turbine wakes as measured by scanning lidar |
| title_full | Three-dimensional structure of wind turbine wakes as measured by scanning lidar |
| title_fullStr | Three-dimensional structure of wind turbine wakes as measured by scanning lidar |
| title_full_unstemmed | Three-dimensional structure of wind turbine wakes as measured by scanning lidar |
| title_short | Three-dimensional structure of wind turbine wakes as measured by scanning lidar |
| title_sort | three dimensional structure of wind turbine wakes as measured by scanning lidar |
| url | https://www.atmos-meas-tech.net/10/2881/2017/amt-10-2881-2017.pdf |
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