Wind Tunnel Study on the Tip Speed Ratio’s Impact on a Wind Turbine Wake Development
We propose an experimental study on the influence of the tip speed ratio on the spatial development of a wind turbine wake. To accomplish this, a scaled wind turbine is tested in a wind tunnel, and its turbulent wake measured for streamwise distances between 1 and 30 diameters. Two different tip spe...
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| Format: | Article |
| Language: | English |
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MDPI AG
2022-11-01
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| Series: | Energies |
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| Online Access: | https://www.mdpi.com/1996-1073/15/22/8607 |
| _version_ | 1797465358833025024 |
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| author | Ingrid Neunaber Michael Hölling Martin Obligado |
| author_facet | Ingrid Neunaber Michael Hölling Martin Obligado |
| author_sort | Ingrid Neunaber |
| collection | DOAJ |
| description | We propose an experimental study on the influence of the tip speed ratio on the spatial development of a wind turbine wake. To accomplish this, a scaled wind turbine is tested in a wind tunnel, and its turbulent wake measured for streamwise distances between 1 and 30 diameters. Two different tip speed ratios (5.3 and 4.5) are tested by varying the pitch angle of the rotor blades between the optimal setting and one with an offset of <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mo>+</mo><msup><mn>6</mn><mo>∘</mo></msup></mrow></semantics></math></inline-formula>. In addition, we test two Reynolds numbers for the optimal tip speed ratio, <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>R</mi><msub><mi>e</mi><mi>D</mi></msub><mo>=</mo><mn>1.9</mn><mo>×</mo><msup><mn>10</mn><mn>5</mn></msup></mrow></semantics></math></inline-formula> and <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>R</mi><msub><mi>e</mi><mi>D</mi></msub><mo>=</mo><mn>2.9</mn><mo>×</mo><msup><mn>10</mn><mn>5</mn></msup></mrow></semantics></math></inline-formula> (based on the turbine diameter and the freestream velocity). For all cases, the mean streamwise velocity deficit at the centerline evolves close to a power law in the far wake, and we check the validity of the Jensen and Bastankhah-Porté-Agel engineering wind turbine wake models and the Townsend-George wake model for free shear flows for this region. Lastly, we present radial profiles of the mean streamwise velocity and test different radial models. Our results show that the lateral profile of the wake is properly fitted by a super-Gaussian curve close to the rotor, while Gaussian-like profiles adapt better in the far wake. |
| first_indexed | 2024-03-09T18:21:22Z |
| format | Article |
| id | doaj.art-4297f4fe133b49789b404d792f5dce7c |
| institution | Directory Open Access Journal |
| issn | 1996-1073 |
| language | English |
| last_indexed | 2024-03-09T18:21:22Z |
| publishDate | 2022-11-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Energies |
| spelling | doaj.art-4297f4fe133b49789b404d792f5dce7c2023-11-24T08:15:43ZengMDPI AGEnergies1996-10732022-11-011522860710.3390/en15228607Wind Tunnel Study on the Tip Speed Ratio’s Impact on a Wind Turbine Wake DevelopmentIngrid Neunaber0Michael Hölling1Martin Obligado2Department of Energy and Process Engineering, Norwegian University of Science and Technology, 7034 Trondheim, NorwayInstitute of Physics and for Wind, University of Oldenburg, 26129 Oldenburg, GermanyCNRS, Grenoble INP, LEGI, Université Grenoble Alpes, 38000 Grenoble, FranceWe propose an experimental study on the influence of the tip speed ratio on the spatial development of a wind turbine wake. To accomplish this, a scaled wind turbine is tested in a wind tunnel, and its turbulent wake measured for streamwise distances between 1 and 30 diameters. Two different tip speed ratios (5.3 and 4.5) are tested by varying the pitch angle of the rotor blades between the optimal setting and one with an offset of <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mo>+</mo><msup><mn>6</mn><mo>∘</mo></msup></mrow></semantics></math></inline-formula>. In addition, we test two Reynolds numbers for the optimal tip speed ratio, <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>R</mi><msub><mi>e</mi><mi>D</mi></msub><mo>=</mo><mn>1.9</mn><mo>×</mo><msup><mn>10</mn><mn>5</mn></msup></mrow></semantics></math></inline-formula> and <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>R</mi><msub><mi>e</mi><mi>D</mi></msub><mo>=</mo><mn>2.9</mn><mo>×</mo><msup><mn>10</mn><mn>5</mn></msup></mrow></semantics></math></inline-formula> (based on the turbine diameter and the freestream velocity). For all cases, the mean streamwise velocity deficit at the centerline evolves close to a power law in the far wake, and we check the validity of the Jensen and Bastankhah-Porté-Agel engineering wind turbine wake models and the Townsend-George wake model for free shear flows for this region. Lastly, we present radial profiles of the mean streamwise velocity and test different radial models. Our results show that the lateral profile of the wake is properly fitted by a super-Gaussian curve close to the rotor, while Gaussian-like profiles adapt better in the far wake.https://www.mdpi.com/1996-1073/15/22/8607wind turbine wakewake modelsexperimental fluid dynamics |
| spellingShingle | Ingrid Neunaber Michael Hölling Martin Obligado Wind Tunnel Study on the Tip Speed Ratio’s Impact on a Wind Turbine Wake Development Energies wind turbine wake wake models experimental fluid dynamics |
| title | Wind Tunnel Study on the Tip Speed Ratio’s Impact on a Wind Turbine Wake Development |
| title_full | Wind Tunnel Study on the Tip Speed Ratio’s Impact on a Wind Turbine Wake Development |
| title_fullStr | Wind Tunnel Study on the Tip Speed Ratio’s Impact on a Wind Turbine Wake Development |
| title_full_unstemmed | Wind Tunnel Study on the Tip Speed Ratio’s Impact on a Wind Turbine Wake Development |
| title_short | Wind Tunnel Study on the Tip Speed Ratio’s Impact on a Wind Turbine Wake Development |
| title_sort | wind tunnel study on the tip speed ratio s impact on a wind turbine wake development |
| topic | wind turbine wake wake models experimental fluid dynamics |
| url | https://www.mdpi.com/1996-1073/15/22/8607 |
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